Patent Publication Number: US-2022233814-A1

Title: Improvements in corrugated catheters

Description:
INTRODUCTION 
     The invention relates to catheters with flexibility and kink resistance, for medical applications such as endovascular procedures. 
     WO2018/011627 (Neuvt Limited) describes various catheters of this type. 
     The invention is directed towards providing improvements to catheters and their manufacture and use. 
     SUMMARY 
     We describe catheters as set out in any of claims  1  to  79 , catheter assemblies as set out in any of claims  80  to  82 , methods of use of an assembly as set out in any of claims  83  to  85 , and methods of manufacture of a catheter as set out in any of claims  86  to  92 . 
     We describe a catheter comprising a jacket and defining a lumen, and extending distally towards a tip, the catheter comprising a helical support within the jacket for at least some of the length of the jacket, wherein the catheter distal end has a plurality of portions of different configurations for different bending and/or pushability characteristics. 
     Preferably, a distal-most portion does not include a helical support. 
     Preferably, a distal-most portion has one or more radiopaque bands. Preferably, a more proximal portion has corrugations which have a smaller depth and/or width. Preferably, a more proximal portion is un-corrugated. Preferably, a more proximal portion has a jacket material of a greater stiffness than a next distal-most portion. Preferably, the jacket includes urethane. 
     Preferably, a more distal portion comprises jacket material including urethane of about 70A to 90A durometer, more preferably about 80A durometer. Preferably, a more distal portion has a floating unbounded helical support. 
     Preferably, a more distal portion comprises inner and outer layers of material such as ePTFE with a helical support unbonded within a helical channel. Preferably, the helical support has a varying pitch in the longitudinal direction. Preferably, the helical support pitch increases distally for at least some of the length of the catheter. 
     Preferably, the helical support pitch increases distally for at least some of the length of the catheter, and there are increases and decreases in stiffness. 
     Preferably, a more proximal portion has a jacket which bonds to the helical support, the helical support being constrained from movement relative to the surrounding jacket material, and the jacket material which bonds to the helical support may include urethane. 
     Preferably, adjoining portions have jackets of differing stiffness, more flexible distally. Preferably, an increased hardness jacket is provided next to a lower hardness jacket, and an increase in the degree of corrugation locally is provided to avoid a sudden increase in stiffness. 
     Preferably, there is a reducing jacket thickness in a more distal portion in order to increase flexibility distally. 
     Preferably, the lumen is provided by a liner. Preferably, the lumen is provided by a liner having different materials joined at a joint. Preferably, the joint is in a portion with an un-corrugated jacket. 
     The lumen may be provided by a liner having different materials joined at a joint, and the liner material transitions from ePTFE to PTFE. 
     The lumen may be provided by a liner having different materials joined at a joint, and the transition or switch is in an area of jacket of higher stiffness or durometer than a most distal portion. Preferably, the lumen is provided by a liner having different materials joined at a joint, and the liner joint or transition is preferably at least 5 cm from the catheter tip. 
     The lumen may be provided by a liner having different materials joined at a joint, and the liner joint spans portions with jackets of different hardness, a distal portion jacket having greater flexibility. Preferably, the lumen is provided by a liner which does not extend to the tip. Preferably, the helical support has a longer pitch closer to the distal end. Preferably, the helical support does not extend to the tip. 
     Preferably, the catheter has a hydrophilic coating over at least one portion. Preferably, the catheter has a hydrophilic coating over at least one portion, and wherein the coating is applied across at least 20 cm of the catheter length. 
     The catheter may have a hydrophilic coating over at least one portion and the coating has a primer layer of material such as urethane. 
     Preferably, the catheter has a hydrophilic coating over at least one portion, and the coating layer or layers are less than 0.002 in in thickness, and preferably the coating thickness is less than 0.001 in in thickness. 
     Preferably, the catheter has a hydrophilic coating over at least one portion, and the coating comprises a hydrogel which fills at least part of the corrugate. 
     Preferably, the catheter has a hydrophilic coating over at least one portion, and the coating comprises a hydrogel which fills at least part of the corrugate, and hydrogel material has a stiffness lower than that of the (e.g. urethane) jacket material, and preferably said filling enables a smooth outer surface, or cushion, for contact with a vessel wall, while the hydrogel provides lubricity without increasing the stiffness of the catheter section significantly. 
     Preferably, the tip of the catheter is expandable to enable it to accept a clot or embolus when a vacuum is applied. The tip may include a radial support such as a stent-like structure which can deform radially to enlarge and engulf the embolus. 
     Preferably, the tip diameter tapers towards the end, but is expandable upon the application of a vacuum and entrance of an embolus into the catheter tip. 
     The catheter may comprise a radial support within the jacket at or adjacent the distal tip, and preferably said support comprises a ring which is not continuous and has a cut. Preferably, the cut is configured so that the radial support can open to allow the distal tip diameter to increase, but cannot reduce in diameter, preserving the lumen of the catheter during vacuum. 
     We also describe methods of manufacture of a catheter as described in any example. The method may include steps of placing a liner of material such as ePTFE on a mandrel, placing a helical support on the liner, and dip coating to apply a corrugated jacket, in which the coating takes the geometry of the liner and the helical support. There may be further dip coating steps to build up the jacket thickness such that the corrugations remain true and do not fill. 
     Preferably, the method including steps of stretching a liner in order to alter the directionality of the liner material (e.g. ePTFE) fibres and reduce the wall thickness as required. The liner may be radially stretched, preferably by at least 10% in diameter. 
     The method may include setting force required to bend the catheter by linear pre-stretching or shortening of the liner and/or jacket material. 
     The method may include etching to improve the potential to bond the jacket to the liner, and/or to induce shortening, and/or working or pre-conditioning the jacket and the liner using a series of bend and/or tension and/or compression cycles to enhance flexibility. 
    
    
     
       DETAILED DESCRIPTION OF THE INVENTION 
       The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only with reference to the accompanying drawings in which: 
         FIG. 1  is a sectional side view of distal portions of a catheter; 
         FIG. 2  is a schematic illustrating dimensions on a cross section of a corrugate geometry of catheters, showing depth of corrugate (d cor ), radius of fillet of corrugate rib (r Rib ), radius of the inside of the corrugate (r Cor ), height of the corrugate (h Cor ), length (or “wavelength”) of a corrugation unit (I cor ), and residual depth (d res ); 
         FIG. 3  is a schematic demonstrating how as a corrugated catheter geometry is bent, in which adjacent corrugations come into contact, increasing force is required to continue to bend the catheter; 
         FIG. 4  is a schematic demonstrating how a larger corrugate depth and height means corrugations will come into contact during bending, increasing the force and energy required to bend the section of corrugated catheter; 
         FIG. 5  is a sectional view showing a portion of a catheter in which there is a more gradual increase in depth of corrugations in the longitudinal direction; 
         FIG. 6  shows part longitudinal sectional views of distal portions of six additional catheters; 
         FIG. 7  shows distal tips of three additional catheters; 
         FIG. 8  shows a proximal encapsulated section and a distal floating coil section in a further catheter; 
         FIGS. 9( a ) and ( b )  are diagrams showing part of the length of a catheter with a hydrophilic coating, showing the difference between dry and hydrated states; 
         FIG. 10  shows a catheter with a deep hydrophilic coating; 
         FIG. 11  shows how a mild corrugated surface may develop in the surface of a hydrophilic coating, in the opposite sense to the underlying jacket material corrugation; 
         FIGS. 12( a ) and 12( b )  show shape effects during bending of a catheter, and possible delamination on the concave side, and  12 ( c ) shows the relative volumes of the recess and the hydrophilic coating within the recess respectively, of a corrugate; 
         FIGS. 13 and 14  show part of a catheter with selective hydrophilic coatings on corrugation ribs, and a manner of application of such coatings; 
         FIG. 15  shows bend parameters; 
         FIG. 16  shows a catheter having a transition from one helical support to another, with a connector element; 
         FIG. 17  shows a catheter having different and interwoven helical supports with different pitches to achieve reduced steps in stiffness in the longitudinal direction; 
         FIG. 18  shows an alternative arrangement with interwoven helical supports; 
         FIG. 19  shows a still further arrangement, in this case with a liner lap joint and interwoven helical supports; 
         FIG. 20  shows a catheter with a liner lap joint and a constant diameter jacket without corrugations in this region of the catheter; 
         FIG. 21  shows an arrangement in which there are transitions from one type of jacket material to another near the location of a lap joint between liners, and helical supports being interwoven across the jacket material joint and the lap joint, and  FIG. 22  shows an alternative with more transitions between jacket materials, and again this region of the catheter does not have corrugations; 
         FIG. 23  shows part of an assembly of a mother and daughter catheter and vacuum fixtures, and  FIG. 24  shows stages of clot retrieval with such an assembly; and 
         FIG. 25  is a diagram showing transitions between catheter portions in a direction from proximal (left) and distal (right) in one example having some of the features illustrated in the other drawings. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Referring to  FIG. 1  this shows the distal portions of a catheter  1  including the following from a tip (distal end) proximally:
         A first portion  10  forming a tip of jacket material  30  with a tapered profile narrowing in the distal direction, and embedding a radiopaque ring  25 .   A second portion  11  with the jacket material  30  encapsulating a helical support  20  (which extends further proximally), and having corrugations  33 .   A third portion  12  with the jacket material  30  encapsulating the helical support  20 , and having shallower corrugations  35 . The corrugations  35  have in this case the same Pitch as the more distal corrugations  33 , but the depth door of the recesses is smaller.   A fourth portion  13  of different jacket material  40  encapsulating the helical support  20  and having a non-corrugated cylindrical outer surface.   A fifth portion  14  of different jacket material  45  and having a non-corrugated cylindrical outer surface  46 .       

     The portions  10 ,  11 ,  12 , and  13  include a liner tube  5  which defines the lumen, and the portion  14  includes a liner tube  3  and a joint  6 . The jacket materials  30 ,  41 , and  45  are different in terms of flexibility being more flexible towards the distal end. 
     For various catheters described here some dimensions defining corrugations are illustrated in  FIG. 2 :
         Pitch is the peak-to-peak longitudinal distance, the wavelength;   W is the width (in the longitudinal direction) of a trough of a corrugation;   d Cor  is the depth of a corrugation trough (or height of a corrugation rib);   r rib  is the radius of curvature of a corrugation rib;   r cor  is the radius of curvature of a corrugation trough;   d res  is the height (radial dimension) of the jacket at the bottom of the trough; and   h cor  is the height (radial dimension) of the corrugation       

     Referring again to the catheter  1  of  FIG. 1 , it has a flexible tip which is more flexible distally than proximally. In the distal portions  10 ,  11 , and  12  the jacket material  30  is urethane bonded to the liner 5 comprising:
         Compressible material or fibrous material.   Preferably ePTFE: Density, thickness per tables below.       

     The more distal portions of the ePTFE lined distal jacket are corrugated and the fourth and fifth portions are un-corrugated. 
     In this example the corrugations are more pronounced, deeper and and/or wider, in at least one more distal portion than in at least one more proximal portion. The recesses are deeper distally than proximally, meaning the residual material beneath the recess is lower distally than proximally. In another embodiment the recesses are constant in depth and width, but the residual material beneath is lower distally than proximally. Once the width of a recess reaches a certain value it may remain constant even as the depth of the recess, and or depth of the residual material beneath the recess is lower distally than proximally. 
     The corrugations represent the impression of a circular wire applied around the outer jacket surface during manufacture. The diameter of the wire is according to the table below in various examples. The corrugations are wide enough to allow a lower bend radius distally than proximally, and are deep enough to allow a lower bend radius distally than proximally without contact between adjacent corrugates (or ribs). 
     The volume of jacket (e.g. urethane) material per unit length of catheter length can vary:
         Being lower distally than proximally, to enhance flexibility.   Being lower distally than proximally such that the height of the rib of the corrugate is controlled so that the outer diameter of the catheter does not increase from at least one portion to the next in the distal direction.   Corrugation geometry is such that the radius of bending at which adjacent corrugations come into contact is lower in the distally than proximally. This may be achieved by controlling the height and width of the corrugation.       

     These attributes are achieved by the physical parameters, especially width, of the corrugation as set out in the tables below, the parameters of which are illustrated in  FIG. 2 . The top surface of the rib is preferably curved. The area between the convex curve of the rib and concave curve of the recess is preferably curved or filleted such that it does not represent a square edge. A square edge is to be avoided as it will cause adjacent corrugations to come into contact at a lower bend radius. A fillet, with a radius r rib  is preferable as shown in  FIG. 2 . 
     In a more proximal portion, the liner material transitions from ePTFE to PTFE. The transition or switch is in an area of jacket of higher stiffness or durometer than the most distal portion. 
     The more distal portion jacket material is preferably in some examples a urethane of about 70A to 90A durometer, more preferably 80A durometer. 
     The liner transition is preferably at least 5 cm from the catheter tip. 
     The most distal portions (length between 0.5 mm to 2 mm) are preferably more flexible, achieved for example by:
         Being corrugated and without any helical support, and/or   Being un-corrugated and without any helical support, and/or   Having a radiopaque marker proximal of a more flexible distal portion.       

     Potential dimensions are outlined for an 8F configuration of the catheter with ID in the order of 2.24 mm (0.088 in). 
     
       
         
           
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                 Attribute 
                 Range 
                 Preferably 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                 Catheter Outer Diameter  
                 2.3-2.7 
                 2.64 
               
               
                 (mm) 
                   
                   
               
               
                 Catheter Inner Diameter  
                 1.7-2.4 
                 2.24 ± 0.1  
               
               
                 (mm) 
                   
                   
               
               
                 Distal Corrugation Depth  
                 &gt;0.025 
                 &gt;0.19, more  
               
               
                 (mm) 
                   
                 ideally ≥0.24 
               
               
                 Distal Residual Depth (mm) 
                 &lt;0.2 
                 &lt;0.1 
               
               
                 Distal Corrugation Width  
                 &gt;0.05-0.51   
                 0.10-0.31 
               
               
                 (mm) 
                   
                   
               
               
                 Distal combined thickness  
                 &lt;0.15 
                 &lt;0.10 
               
               
                 of liner and residual jacket  
                   
                   
               
               
                 (mm) 
                   
                   
               
               
                 Recess Geometry 
                 Round, U, V,  
                 U 
               
               
                   
                 Square 
                   
               
               
                 Rib Geometry 
                 Avoid square  
                 Rounded edge, or 
               
               
                   
                 profile 
                 inverted U 
               
               
                 Rib fillet radius (r rib ) (mm) 
                 &gt;0.025 
                   
               
               
                 Length of Corrugated  
                 &gt;2 
                 &gt;6 
               
               
                 Section (cm) 
                   
                   
               
               
                 Length of Uncorrugated  
                 &gt;1 
                 &gt;4 
               
               
                 Section of Distal Jacket (cm) 
                   
                   
               
               
                 Liner Material 
                 Fibrous or  
                 ePTFE 
               
               
                   
                 compressible 
                   
               
               
                 Liner Density (g/cm 3 ) 
                 0.4-1.2 
                 &lt;0.8 
               
               
                 Liner Thickness pre- 
                 0.025-0.102 
                 &lt;0.076 
               
               
                 assembly (mm) 
                   
                   
               
               
                 Liner Strike Layer 
                 None or TPU or 
                 Polyamide 35D 
               
               
                   
                 Polyamide 
                   
               
               
                 Liner Condition on Mandrel 
                 Radially  
                 Radially stretched, 
               
               
                 Distal Section of Tip 
                 Stretched 
                 Axially Compressed 
               
               
                 Liner Condition on Mandrel 
                 Radially  
                 Radially Stretched 
               
               
                 Proximal Section of Tip 
                 Stretched 
                   
               
               
                 Uncoiled section 80A length 
                 0.5-2   
                 0.5-1   
               
               
                 (mm) 
                   
                   
               
               
                 Helical Support Diameter  
                 0.076-0.127 
                 0.102 
               
               
                 (mm) 
                   
                   
               
               
                 Location of Corrugated  
                 Within 80A  
                 Within 80A  
               
               
                 Section 
                 section  
                 section 
               
               
                 Location of ePTFE and  
                 Proximal  
                 Proximal to 80A 
               
               
                 PTFE Joint 
                 to corrugated  
                 Section, or within  
               
               
                   
                 80A section 
                 40D Section 
               
               
                 Distance of ePTFE and  
                 &gt;0.5 
                 &gt;1 
               
               
                 PTFE Joint within 40D,  
                   
                   
               
               
                 from 80A (cm) 
                   
                   
               
               
                 Type of Joint of ePTFE and 
                 Overlap or Butt 
                 Overlap 
               
               
                 PTFE 
                   
                   
               
               
                 Corrugation Pitch (mm) 
                  0.13-0.076 
                 0.38-0.63 
               
               
                 Corrugated Section Length  
                 &gt;2 
                 &gt;6 
               
               
                 (cm) 
                   
                   
               
            
           
           
               
               
            
               
                 Variance in depth, width of 
                 Variable along length  
               
               
                 corrugation 
                 (increasing distally) 
               
            
           
           
               
               
               
            
               
                 Cinch Wire Diamete (mm) 
                  0.2-0.040 
                   
               
               
                 Winding Tension Applied to 
                 &gt;0.5 
                 &gt;0.5 
               
               
                 Cinch Wire at Proximal End  
                   
                   
               
               
                 (N) 
                   
                   
               
               
                 Force Applied at Distal End 
                 &gt;7 
                 &gt;10 
               
               
                 (N) 
                   
                   
               
               
                 Distal Jacket Material 
                 TPU or Pebax 
                 80A TPU 
               
               
                 Proximal Jacket 1 ID Pre 
                 &gt;2.5 
                   
               
               
                 Lamination (mm) 
                   
                   
               
               
                 Proximal Jacket 1 Thickness  
                 &gt;0.102 
                 0.15-0.20 
               
               
                 Pre Lamination (mm) 
                   
                   
               
               
                 Distal Jacket ID Pre  
                 &gt;2.5 
                   
               
               
                 Lamination (mm) 
                   
                   
               
               
                 Distal Jacket thickness  
                 0.076-0.175 
                 &lt;0.127 
               
               
                 Pre-Lamination (mm) 
                   
                   
               
               
                 ePTFE Liner Inner Diameter 
                 0.76-2.4  
                 1.3-1.8 
               
               
                 Stretching for Pre-Placement  
                   
                   
               
               
                 on Mandrel (mm) 
                   
                   
               
               
                 ePTFE Liner Inner Diameter 
                 1.7-2.4 
                 2.24 ± 0.1  
               
               
                 Post Stretching for Pre- 
                   
                   
               
               
                 Placement on Mandrel (mm) 
                   
                   
               
               
                 ePTFE Liner Condition on 
                 Radially  
                 Radially and 
               
               
                 Mandrel Proximal 
                 Stretched 
                 Longitudinally 
               
               
                   
                   
                 Stretched 
               
               
                 Cinch Wire Shape 
                 Round, Square,  
                 Round 
               
               
                   
                 or Angled 
                   
               
               
                 Length of Overlap (cm) 
                 1-3 
                 1 
               
               
                   
               
            
           
         
       
     
     Table 1—Example dimensions. Dimensions are indicative of an 8F OD, 0.088 ID catheter. They may be scaled up or down depending on the required ID (internal diameter) and (external diameter) OD of the catheter i.e. the same or similar ratios of dimensions may be applied for larger or smaller ID and OD catheters. 
     Corrugation Geometries During Bending 
     Consider a corrugated catheter in bending as shown in  FIG. 3 . For lower degrees of bending A-B adjacent corrugations will not be in contact. During this phase of bending the force required is relatively low. Eventually as further bending is applied the corrugations will come into contact (C), or bottom out. At this point the force required to bend the catheter will increase substantially. In order to maintain a low force during bending it is advantageous to ensure adjacent corrugations do not come into contact for the largest degree of bending deformation possible (i.e. the lowest bend radius). This will allow the catheter to navigate the vasculature at low force, without the potential for vessel damage or perforation. It also decreases the amount of energy required to push the catheter along an area. 
     Contact between adjacent corrugations may be avoided by reducing their height (h cor ) and depth (d cor ) as shown in  FIG. 4 . The desired dimensions will depend on the degree of flexibility and radii of curvature of the target anatomy in which the catheter will be used. Preferable dimensions are outlined in Table 1 above. Referring to the letters A, B, and C, in  FIG. 4  the plots The plots show two corrugation geometries; the first in which the adjacent corrugations have come into contact, and a second where the width of the corrugations has been increased to prevent corrugations coming into contact at the equivalent amount of bending, thus allowing increased bending to take place at a lower Force. 
     In one embodiment a round edge, or fillet, is present on the rib to avoid a square edge (r rib ). This will mitigate contact between adjacent corrugates. A larger fillet will enable adjacent corrugations to come into contact a lower bend radius. Preferable dimensions are outlined in Table 1. 
     In another embodiment, the rib shape is more akin to an inverted V shape or saw-tooth. This significantly mitigates contact between adjacent corrugates. The angle of the inverted V should be greater than 10° to achieve this effect. 
     Width of the corrugate is also important, because in the absence of a corrugation width (W), or relatively wide recess, the catheter may not achieve significant flexibility, and low forces of bending. Preferable dimensions are outlined in Table 1. Increasing corrugate width also has the effect of mitigating contact between corrugates. 
     Polymers used in catheter manufacture are, in the main, incompressible materials. This means that, as they are deformed the volume of material remains substantially constant. In one process of manufacture the outer layer of material is corrugated using a cinch wire. The cinch wire is under tension such that an impression is made on the outer layer. As the tension is increased the cinch wire will displace material under the wire thereby creating a recess and forcing the material into a less constrained region, creating a rib. This rib and recess configuration enables improved flexibility since residual depth (d r ) is reduced,  FIG. 2 . Heating may be used to permanently set the rib and recess configuration prior to removal of the cinch wire. 
     While increased tension on the cinch wire will deepen the impression of the corrugation resulting in a lower residual depth (d r ), it will also increase the height of the corrugation (h cor ) such that the outer diameter of the catheter increases in that region. Furthermore, it will increase the width of the corrugation to limit approaching the diameter of the cinch wire. It should be noted that following heat setting and removal of the cinch wire some relaxation of the polymer occurs, typically leaving maximum corrugate width which is less than that of the diameter of the cinch wire, usually of the order of 50% to 95% of the cinch wire. For 80A pellethane this is of the order of 75% of the diameter of the cinch wire. This geometry is shown schematically in  FIG. 5  and  FIG. 2 . 
     This will increase the outer profile of the catheter meaning it requires a larger arteriotomy (hole) for insertion. The residual depth shown in  FIG. 5  is the combined depth of the liner and jacket. While the corrugations are shown as defined ribs and recesses representing a repeating unit, undulations and perturbations may be present on the repeating pattern as shown. Hence corrugations may not always be an exact repeating unit. 
     Particularly in the case of more distal tortuous anatomy, it may be required to achieve a lower bend radius distally than proximally. Similarly, more stiffness and pushability may be desirable proximally than distally. 
     The volume of jacket material across a length of the catheter may be altered locally to avoid an increase in corrugate height. In one configuration the volume of the jacket material is tailored such that the outer diameter of the catheter is maintained constant along a section of catheter, while the residual depth of the corrugations is reduced. The volume of the jacket may be reduced by reducing its thickness. 
     Reducing the thickness of the jacket also serves to reduce the residual depth following application of the cinch wire at a given tensions, further improving the flexibility of the catheter. 
     In another configuration, a lower volume of jacket material per unit length is used in a more distal region compared to a more proximal region to achieve a lower rib height distally than proximally. This allows for a lower outer diameter of the catheter distally than proximally, in tandem with a deeper corrugation. This further reduces the change of contact between adjacent corrugates during bending. 
     Other arrangements are shown schematically in  FIG. 6 . In order from top to bottom: 
     Catheter  200 : This has joint or overlap  243  of distal ePTFE liner  240  and proximal PTFE liner  241  within an un-corrugated portion  220 . The proximal portion  220  has a jacket material  221  which is less flexible than the more distal jacket. Alternatively,  220  may represent an uncorrugated portion of the distal most jacket material. The joint  243  has a short overlap, such that there is a region of single layer of PTFE proximally, and ePTFE distally within that portion  220 . Otherwise, this catheter  200  has portions from the distal end proximally:
         First, or tip portion  201  with corrugations  202  in a jacket  203  and within which there is a helical support  204 .   Second portion  210 , with shallower corrugations  211 .   Third portion  220 , with un-corrugated jacket material  221 , and surrounding the liner joint  243  between the ePTFE distal liner tube  240  and a proximal liner tube  241 .   Fourth portion  230 , with cylindrical un-corrugated jacket material  231 .       

     Catheter  250  has a liner joint or overlap  290  of a distal ePTFE liner  291  and a proximal PTFE liner  291  which spans portions  270  and  280  with jacket materials  271  and  281  of different durometer. This has a first portion  251  with corrugations  253  in a jacket  252 , a second portion  260  with shallower corrugations  261 , a third portion  270  with un-corrugated jacket material  271 , and a fourth portion  280  which is also un-corrugated. The liner joint  290  spans the portions  270  and  2280  with jackets of different hardness, the distal portion jacket  271  having greater flexibility 
     In other examples, the lap joint may be located in any region or may span any two more regions of different jacket material. 
     Catheter  300  has a first portion  301  with a jacket material  303  of 80A hardness with corrugations  302 , a second portion  310  with corrugations  312  of shallower depth, a third portion  320  with a different jacket material  321  and shallower corrugations  323 , a fourth portion  330  of un-corrugated jacket material  331  of hardness 40D to 55D, and a fifth portion  340  with un-corrugated jacket material  341  of hardness 55D to 72D. In this case the lumen is formed by a distal liner of ePTFE which does not extend to the tip and which is joined in the fifth (proximal-most portion shown) to a PTFE proximal liner. In this embodiment any proximal jacket may be of a larger wall thickness than and more distal jacket such that it results in a stiffer portion of the catheter. 
     Catheter  350  has a first portion  351  with a jacket  352  without a helical support adjacent the tip. A second portion  360  has shallower or equal corrugations and the same jacket material  352 . A third portion  370  with more shallow corrugations and the same jacket material  352 . A fourth portion  380  has un-corrugated jacket material  381  which is stiffer or equal to the distal most jacket, and a fifth portion  390  has un-corrugated jacket material  391  of 40D to 55D or greater hardness. A liner joint is within the fifth portion  390 . The first portion does not include a helical support. 
     In another embodiment the portion without a helical support may comprise un-corrugated jacket material such as un-corrugated 80A jacket material. 
     Catheter  400  has first, second, third, fourth, and fifth portions  401 ,  410 ,  420 ,  430 , and  440 . The first portion  401  does not include a helical support but has two marker bands or rings for radiopacity and to provide radial support. 
     Catheter  450  has first, second, third, fourth, and fifth portions  451 ,  460 ,  470 ,  480 , and  490  respectively. In this case a helical support  452  has s smaller pitch in the more proximal portions. 
     Jackets of intermediate hardness to those described may be used, or by blending these durometers described above. 
     Where an increased hardness jacket is used next to a lower hardness jacket, an increase in the degree of corrugation locally may be used to avoid a sudden increase in stiffness. 
     These examples have some or all of the following attributes:
         Reducing the wall thickness of the catheter wall or jacket in a more distal portion in order to manage flexibility.   Corrugation of more than one jacket.   Terminating the liner some distance proximal to the tip of the catheter.   Use of a corrugated area distally without a helical support.   Use of an uncorrugated area distally without a helical support.   Use of marker band for internal support at the distal tip (shown as rectangular cross section). These may be of a helical geometry of multiple pitches or are discrete circular rings of material.   Use of varying pitches of helical support, increasing periodically in increase stiffness.       

     Distal Tips 
     It may be preferable to have even more flexibility within the distal end of the catheter, such as the final 5 mm to 10 mm of the catheter. This is to ensure that the tip does not snag on the vessel wall and can track tortuous anatomy with or without the support of an internal catheter or wire. To achieve this, a number of approaches may be taken as outlined in  FIG. 7 . 
     In one example ( 500 ), the pitch of the helical support ( 510 ) is increased substantially such that one or more ribs of the corrugation are comprised of jacket material only, towards a tip  505 . A liner  501  extends all of the way to the tip. 
     In another example ( 600 ) the helical support ( 610 ) is terminated such that one or more ribs of the corrugation in series comprise polymer only at the tip ( 605 ). Again, a liner  601  runs the full length to the tip. 
     In one configuration ( 700 ) a leading edge ( 705 ) of un-corrugated polymer without the presence of helical support ( 710 ) is used. A radiopaque marker band ( 706 ) may or may not be present in any of the above configurations. The region without a helical support may be corrugated or un-corrugated in any of the above configurations. 
     In at least some of these examples the first portion at the tip has a tapered outer surface, narrowing distally. 
     Dip Coating 
     In one method of manufacture, an ePTFE liner is placed on a mandrel. A helical support is placed on the liner. Dip coating is then used to apply a corrugated jacket, in which the coating takes the geometry of the liner and helical support. Multiple steps may be used to build up the jacket thickness such that the corrugations remain true and do not fill. 
     Liner Condition 
     ePTFE is a material which by its fibrous and/porous nature, can be stretched at least to some extent. During its manufacture, it can be difficult to control the wall thickness of the ePTFE liner. 
     Stretching may be performed in order to optimise the ePTFE liner for use in the catheter. This stretching can alter the directionality of the fibres and reduce the wall thickness as required. In one embodiment, the liner is radially stretched, by at least 10% in diameter. 
     When a catheter is in bending, there is a neutral axis, above which compression of the catheter wall is present, and below which tension is present. 
     To increase the force required to bend the catheter linear pre-stretching of the ePTFE on a mandrel may be performed. This removes “slack” or redundancy from the structure. Similarly shortening (to introduce slack) may be performed to reduce the force during bending. In one embodiment the liner is shortened by at least 10% in the distal region of the catheter tip in order to ensure a low force during bending. 
     In one method of manufacturing, etching is used to improve the potential to bond to the ePTFE liner, and to induce shortening. In one embodiment shortening of at least 10% is present in the ePTFE liner within 5 cm of the distal tip. More proximally the liner does not embody any shortening or is the liner is stretched. 
     A further characteristic of the fibrous liner is that it may be deformed beyond an elastic region. Beyond this elastic region the force required to further deform the liner is lower. Because of this, an ePTFE lined catheter may be “worked”, or pre-conditioned using a series of bend and/or tension and/or compression cycles to enhance its flexibility. 
     In one embodiment, the catheter is pre-conditioned using bend and/or tension and/or compression cycles to enhance its flexibility. 
     Hybrid Device 
     The catheters described here achieve improved pushability arising from features such as corrugated urethane design with encapsulated helical support. 
     In one embodiment the distal end comprises distinct portions:
         Proximal Encapsulated Portion: A corrugated section in which helical coil is embedded in a layer of urethane; the helical support being constrained from movement relative to the surrounding jacket material.   Distal ePTFE Floating portion: A corrugated section comprising an inner and outer layer of ePTFE with a helical support unbonded within helical channel   The inner layer of ePTFE on the distal tip continues as a liner for the corrugated 80A section.       

     An example is shown in  FIG. 8( a ) , which shows the distal end of a catheter  800 , with a first portion  801 , a second portion  810 , a third portion  820 , and a fourth portion  830  in the direction from distal to proximal. In the first portion  801  the coil  802  is floating, whereas in the second portion  810  it is embedded in jacket material  811 . 
     In  FIG. 8( b )  a configuration is shown in which the inner layer  901  of ePTFE on the distal tip continues as a liner for the corrugated 80A section. Further proximally the liner forms part of a lap joint  902  with a different liner  903  more proximally. In the configuration shown the inner layer of the distal tip overlaps itself as a double layer for a section before being a single layer within the 80A corrugated section. 
     In one example the distal floating arrangement has a length of at least 5 mm, preferably between 5 mm and 50 mm, more preferably between 5 mm and 20 mm. 
     Hydrophilic Coating 
     The catheter may have a hydrophilic coating over at least a portion. Hydrophilic coatings significantly reduce the amount of friction between the vessel wall and the catheter, allowing the catheter to be advanced or withdrawn without excessive effort. Furthermore, reduced friction means the transfer of displacement from the hub to the tip of the catheter is more efficient allowing more precise navigation by the physician. 
     Preferably the coating is applied across at least 20 cm of the length. Some coatings require the application of a primer layer typically comprised of a urethane, and an outer lubricous coating. The thickness of these layers should be minimised to avoid altering the stiffness of the tip. Any filling of the corrugation will reduce its effectiveness in achieving a flexible catheter section. In one configuration the coating layers are less than 0.002 in in thickness. Preferably the coating thickness is less than 0.001 in in thickness. 
     In one configuration the coating comprises a hydrogel which fills the corrugate. The hydrogel material has a stiffness much lower than that of the urethane jacket material of the catheter. Filling the corrugations will enable a smooth outer surface, or cushion, for contact with the vessel wall, while the hydrogel will provide lubricity without increasing the stiffness of the catheter section significantly. Such materials include but are not limited to poly(vinyl alcohol)-poly(acrylic acid) hydrogels. 
     Expandable Tip 
     In one configuration the distal tip of the catheter may expand or deform to enable it to accept a clot or embolus. That is to say, the most distal portion of the catheter is radially expandable such that during navigation to a target vessel it has a lower profile than when allowing a clot or other device to be pulled into the tip. This allows the tip to behave like an anaconda. 
     In one embodiment the tip of the catheter has a reduced radial stiffness compared to a region proximally, such that it can expand during entry of another body into its tip. In one embodiment the tip has a reducing wall thickness and or stiffness allowing greater radial expansion than a more proximal region. 
     In one embodiment the catheter is configured such that when a vacuum is applied pulling an embolus into the catheter tip, the most distal area expands, helping to engulf and deform the clot for entry into the proximal body of the catheter. 
     In one embodiment, the distal tip has a radial support preventing the tip from collapsing under vacuum, but allowing expansion upon entrance of a body larger than the diameter of the distal tip. The radial support in the tip may comprise a stent-like structure which can deform radially to enlarge and engulf the embolus. 
     In another configuration, the distal tip diameter tapers towards the end, but is expandable upon the application of a vacuum and entrance of an embolus into the catheter tip. 
     In another configuration, the radial support within the jacket at the distal tip comprises a ring which is not continuous and has a cut. This cut means that the radial support can open allowing the distal tip diameter to increase, but cannot reduce in diameter, preserving the lumen of the catheter during vacuum. 
     Coating 
     In general, following hydration, hydrophilic coatings swell and so take up a greater volume of space than when in the dry state as shown in  FIGS. 9( a ) and ( b ) . In these drawings a portion of a catheter  1000  is shown, in which there is a jacket having a jacket body  1001  and a liner  1002  defining the lumen and an outer coating  1003 . A helical support  1004  is within the jacket. The coating  1003  has a greater thickness  1005  when wet than dry. A greater degree of swelling may decrease the effective depth of the corrugations. This provides a smoother outer surface, with slightly less exaggerated corrugate geometry as shown in  FIG. 9( b ) . This may be advantageous in navigation as it creates a smooth surface for interaction with the vessel wall. 
     An extreme example of this is shown in  FIG. 10 , for a catheter  1050  having a liner  1051 , a jacket body  1052 , a helical support  1054 , and a hydrophilic coating  1053 . The coating  1053  has swollen to fill the recess entirely, providing an un-corrugated outer surface. 
     For interfacial friction, increased area of contact increases the force required to overcome the friction. Accordingly, some corrugation pattern is preferable to reduce the area of contact while providing a relatively smooth interfacial surface. 
     In one example sufficient coating volume is present such that when hydrated the coating may swell outside the corrugate to some height above the top of the coated rib as shown in  FIG. 11  for the catheter portion  1050 . In this instance the coating creates a corrugation pattern atop the corrugation pattern of the base catheter, in which the jacket &amp; coil define the corrugation pattern. The coating when hydrated creates a corrugation pattern which is the inverse of the corrugation pattern of the underlying jacket. In  FIG. 11 , the coating rib is 1058 and the recess is 1059. This is achieved by applying a sufficient volume of coating such that the height of the rib is lower than the adjacent height of the recess in the hydrated state. The following specifications apply in respect of the coating being hydrated, for example in water, saline, or blood. Specifically, hydrophilic coatings such as polyethely glycol, polyvinyl pyrrolidone or such derivatives may be used. Derivatives of phosphoryl choline, such as 2-methacryloxyethylphosphorylcholine in acrylic copolymers and water soluble polyvinylethers as well as hyaluronic acid may be also be tailored to achieve the following embodiments. 
     A benefit of a coating such as shown in  FIG. 11  is that it the area of contact with the vessel is reduced thereby aiding navigation of the device. 
     Catheters described may be subject to extreme bending such that adjacent corrugations come closer together, or even into contact, reducing the space or volume within the recess as shown in  FIG. 3 . During this bending some of the coating may be compressed and squeezed out of the corrugation, becoming damaged or delaminating from the catheter wall and or coating matrix. 
     Coating Volume Minimization—Wet State 
     We describe coatings which swell in water to function as a hydrogel while remaining bound to the substrate (in this case the corrugated catheter wall). Poor adhesion or excessive deformation of the coating may cause it to shed, thus increasing the risk of embolism. During bending in navigation, the catheter is subject to tensile forces on the outside of the bend, and compressive forces on the inside of the bend as shown in  FIGS. 12( a ) and 12( b )  in a catheter portion  1100 . This has a concave (lower as illustrated) side and comprises a liner  1101  a jacket body  1102 , a helical support  1103  and a coating  1104 .  FIG. 12( b )  shows at  1108  coating deformation and at  1107  coating delamination. While the coatings remain intact on the tensile (top, convex) side of the bend, on the compressive side significant coating damage may be induced as adjacent corrugates can squeeze the coating between the ribs, eventually causing delamination. 
     Furthermore, adjacent corrugations coming into contact may increase the force required to cause bending and stiffening the catheter. To mitigate these issues the amount of coating within the corrugate may be minimized while maintaining sufficient lubricity, as shown in  FIG. 12( a ) . 
       FIGS. 12( a ) and ( b )  shows how, during bending, compression may deform and squeeze the coating. which may cause delamination of the coating from the rest of the coating itself or from the jacket substrate. The constituents of the coating may be tailored to adjust the degree of swelling which takes place when hydrated. 
       FIG. 12( c )  shows at  1150  the volume of a recess and at  1155  the coating volume within the recess. In one example, the volume of coating is such that when in the hydrated state the ratio of hydrated coating volume within the recess to underlying recess volume per unit catheter length is less than 0.9, preferably less than 0.5, and more preferably less than 0.2, and even more preferably less than 0.1. In one configuration the thickness of the coating in the hydrated state is less than 0.05 mm, preferably less than 0.02 mm, more preferably less than 0.015 mm. In other examples, the coating has a thickness such that when hydrated its thickness at the bottom of the rib is less than 25% of the corrugate depth and or width, preferably less than 15% of the corrugate depth and or width, and even more preferably less than 10% of the corrugate depth and or width. 
     In other examples, the coating has a thickness such that when hydrated its thickness at the bottom of the rib is less than 20% of the height of the corrugate (h cor ), preferably less than 12% of the, and even more preferably less than 10%. 
     Coating Volume Minimization—Dry State 
     In one embodiment the thickness of the coating in the dry state is less than 0.010 mm, preferably less than 0.008 mm, more preferably less than 0.006 mm. In another embodiment, the dry thickness of the coating is less than 10% of the corrugate depth and or width. In another embodiment, the dry thickness of the coating is less than 3% of the corrugate depth and or width. 
     Selective Coating of Upper Section of Ribs 
     In general, the only portion of the corrugate which is in contact with the vessel wall is the upper section of the corrugate (the rib). The coating may be selectively applied to this area. This mitigates the potential for adjacent corrugates or areas of coating to come into contact during bending. 
     As shown in  FIG. 13  in a catheter portion  1200  there is a liner  1201 , a jacket body  1202 , a helical support  1203 , and a hydrophilic coating  1204  in a spiral pattern on the rib ridges. This is achieved by use of a masking element such as a wire  1205  shown in  FIG. 14  to prevent application of the coating to the recess area of the corrugate. This leaves only the rib area exposed during application of the coating. In this example, the recess region of the corrugate is masked off using a wire or other means as shown in  FIG. 14 . The catheter is then coated by dipping, spray or other methods. 
     The coating may then be left to cure or dry. Subsequently the masking element is removed leaving coating behind on the convex portion of the corrugate only as shown in  FIG. 13 . Alternatively, the masking may be removed before the coating has dried. 
     Corrugate Size and Bending 
     In one embodiment, the volume of coating is limited such that in the hydrated state adjacent ribs do not come into contact during bending. In another embodiment adjacent corrugations may come into contact at a desired radius, but without any squeezing of the coating from within the corrugate. 
     In one embodiment, the jacket and coating are configured such that adjacent corrugates only contact one another at a certain the centre-line radius of curvature of the catheter in bending.  FIG. 15  shows a catheter portion  1250  with segments  1251  and  1252  extending from a bend  1253  with a centre-line radius  1254  and an outer diameter  1255 . In this case the radius  1254  is less than or equal to 2 times the diameter  1255  of the catheter, preferably less than or equal to 1 times the diameter of the catheter, and more preferably 0.7 times the outer diameter of the catheter. 
     In another embodiment, the coating and jacket are configured such that adjacent hydrated corrugates only contact one another when the centre-line radius of curvature of the catheter in bending is less than or equal to 2 times of the diameter of the catheter, preferably at least 1 times the diameter of the catheter, and more preferably 0.7 times the outer diameter of the catheter. 
     Distal Tip and Proximal Shaft Joint 
     In some examples, the helical support in a distal portion of the catheter includes a super-elastic material such Nitinol, while the helical support in a more proximal portion includes a stiffer material such as stainless steel. This is to allow a flexible durable and kink resistant section distally and a stiffer section proximally to provide pushability and support. 
     In one example the catheter includes two portions as follows:
         a more distal portion with:
           a liner,   an outer jacket being corrugated in at least one area,   a more proximal region which is less corrugated or un-corrugated, and   a helical support: and   
           and a more proximal portion with:
           a different liner to the one in the distal portion,   an outer jacket which is not corrugated, and   a helical support or braid which is stiffer than the support in the distal portion.   
               

     The distal and proximal regions of the catheter may be manufactured separately on individual mandrels and joined afterwards. Alternatively, they may be laid up on the one mandrel and reflowed to form a single unit. The more distal portion liner may be of primarily ePTFE, and the more proximal liner may be of primarily PTFE. 
     Alternatively, both the liner proximally and distally may be comprised of PTFE or ePTFE. This may be required in a situation in which two liners of the same material but of different thickness must be joined. Or in the case of ePTFE two different thicknesses and/or densities may be used proximally and distally. 
     Change in Type of Coil 
     The transition from a helical support of one type to another presents a challenge in terms of ensuring a stable joint, preventing kinking, and wire protrusion during manufacture and when the catheter is in use. Use of differing support wires (e.g. Nitinol and stainless steel) allows differing degrees of stiffness, dimensions, and ability to accommodate deformation elastically. A number of approaches are described here to ensure joint stability. 
     In one example it is preferable that the helical supports have the same direction of winding, both being right-handed or left-handed. This allows continuity of coil support, thereby reducing potential for stress concentrations. 
     The two types of helical support (or “coil”) may be joined by a connecting element such as a weld. In one such configuration, the ends of the helical wires are joined end-on-end with a butt weld, while in another configuration they are bonded side-by side as shown in  FIG. 16 . In this catheter  1300  there is a first helical support  1301 , a second helical support  1302  both on a jacket body  1304 , and the supports being joined by a connecting element  1303 . The connecting element  1303  is a hypo-tube crimped onto the ends of the wires  1301  and  1302  either side-by-side or end-on-end. The helical supports may be stabilized using a glue (such as Dymax™ UV cured adhesive or cyanacrylate). 
     It is advantageous to avoid sudden increase in stiffness in this region. In these situations, it is preferable to achieve increasing stiffness from distal to proximal regions. This allows transmission of force and displacement without buckling or kinking. Hence the embodiments described here and indicative stiffness associations are shown. 
     In one configuration the helical supports both being of the same direction of wind are wound within one another for at least one pitch as shown in  FIG. 17 , preferably for at least 2 pitches, more preferably at least 5 pitches, and even more preferably at least 10 pitches. This may be referred to as an interwoven configuration. In  FIG. 17  a catheter  1400  has a liner  1401 , a first helical support of relatively small wire diameter  1402 , and a second helical support or relatively large wire diameter  1403  which are inter-woven in a region  1404 .  FIG. 17  also shows a plot representing change in stiffness along the catheter from the distal section (left) to the proximal section (right) for the configuration shown. The first helical support  1402  represents a distal region of the catheter, while the second helical support  1403  is in a more proximal region of the catheter, and the distal helical support being of flexible (e.g. of Nitinol) and the proximal support being stiffer (e.g. of stainless steel). 
     If the helical supports are at the same pitch in the interwoven region as in their more proximal and distal regions there will be an increase in catheter stiffness in this area due to the presence of excess material which reduces catheter flexibility. It can also cause a propensity for kinking at the areas at either end of the interwoven region where the stiffness abruptly drops. This may be mitigated by adjusting the pitch of one or both helical supports in the interwoven region. In this example, the pitch of the stiffer coil (second helical support  1403 ) is larger in the interwoven region (Pitch 3,  1412 ) than outside the interwoven region (Pitch 4,  1413 ). This region of larger pitch is wound partially or entirely within the less stiff helical support. The pitch of the more flexible coil (first helical support  1402 ) is larger in the interwoven region (Pitch 2,  1411 ) than outside the interwoven region (Pitch 1). This region of larger pitch is wound partially or entirely within the more stiff helical support. The pitch of both the first and second helical coil is larger in the interwoven region (Pitch 2 and Pitch 3,  1411 ,  1412 ) than their respective pitches in the distal and more proximal areas (Pitch 1 and Pitch 4,  1410 ,  1413 ). The associated change in catheter stiffness is shown in the plot of  FIG. 17 . 
     More preferably the pitch of each support in the interwoven region is 2× times the pitch of the support outside the interwoven region. Thereby, when both coils are interwoven the space between adjacent turns of the wire can be consistent across all three regions of the joint as shown in  FIG. 17 . 
     In one example, one or both helical supports are fixed in place using a low-profile heat shrink such as PET with a thickness of 0.2 mm or less, preferably 0.025 mm or less. This may be encapsulated using polymer jacket flowed over the area in subsequent manufacturing steps. 
     Improved pushability and torqueability of the catheter can be achieved by having a braid support over some or all of its length. In one configuration the proximal portion of the catheter has a braid support while the distal portion contains a helical wire. “Pushability” is defined as the ability to transmit force from the proximal end of the catheter to the distal end of the catheter. “Torquability” is defined as the ability to transmit a rotation and or rotational force (torque) from the proximal end of the catheter to the distal end of the catheter. 
     In one example the helical support in the distal section is a continuation or extension of one of the wires from the proximal braid, while the other wires of the proximal braid wires have been terminated at the start of a distal section. 
     In one configuration the pitch of the extension wire from the braid reduces at or near the point of termination of the other braid wires. In one embodiment the extension wire of the braid is of larger cross section than the other wires in the braid. In another embodiment the extension wire of the braid, and at least one other wire of the braid is of larger cross section than the other wires in the braid. 
     In one other configuration the right-handed coils within the braid are terminated at a point beyond which the left-handed coils of the braid continue distally. 
     In another configuration the extension wire from the proximal braid, representing a second helical support is continued to overlap into the distal section of the catheter, and changes to a different (first) helical support using one of the means outlined above and according to  FIG. 17 . 
       FIG. 18  shows a catheter  1425  with a first helical support  1426 , a second helical support  1427 , and a liner  1428 . The jacket body is not shown. There are first, second, third, and fourth pitches  1429 ,  1430 ,  1431 , and  1432 . The second pitch  1430  is the pitch of the first support  1426  being longer than the pitch of this support when not overlapped. Likewise, the third pitch  1431  is the overlapped pitch of the second support  1427 , again being longer than that of this support alone ( 1432 ). 
     Change in Type of Liner 
     As shown in  FIG. 6 , a lap-joint may be used at the transition from one liner to another, in this case liners of ePTFE and PTFE material. Preferably, the inner diameter of the ePTFE liner is in contact with the outer diameter the PTFE liner. In one configuration the PTFE liner has an outer strike layer to improve its bond to the ePTFE liner. The strike layer has a thickness of less than 0.025 mm, more preferably 0.005 mm to 0.010 mm. 
     In one configuration the inner diameter of the ePTFE liner is etched in the region at which it overlaps the PTFE liner with a strike layer  1458  on its outer diameter as shown in  FIG. 19 . A number of approaches may be used to apply the etch, including a sodium-based etching solution such as Fluoro-Etch™, or via a process such as plasma etching. 
     The strike layer applied to the PTFE may include a soft thermoplastic such as polyerther block aimide (Pebax™) or nylon or other polymer materials. Softer durometer strike layers may be more suitable to flexible portions of the device. In one configuration the strike layer on the PTFE is the same material as the outer jacket to which it is bonded. Strike layers may be applied to the outer side of the PTFE, and/or to the inner side of the ePTFE, in the configuration where the ePTFE is on the outside. 
     The lap joint is an area at which the outer diameter of the catheter and stiffness increase due to the overlapping thickness of the ePTFE and PTFE. Accordingly, the length of this lap joint should be as short as possible to maintain a low profile and flexible catheter, but long enough to ensure a good bond between the two liners. In one configuration the length of this joint is between 1 and 5 mm, preferably between 10 and 20 mm for an 8F catheter. Preferably the lap joint is at least 1 diameter in length, more preferably at least 2 diameters in length. 
     Joint Location 
     The change in liner type from a first liner (Liner) 1 to a second liner (Liner 2) may take place at the same location as the change in the helical support type. That is to say, the change in helical support type is present close to or over the region of change in liner type. To prevent stress concentrations, it is preferable to avoid multiple joints or changes in material on top of one another. 
     In one configuration, the transition from Liner 1 (ePTFE) to Liner 2 (PTFE) takes place proximal to the transition via an interwoven region from a flexible helical support to a stiffer helical support. In a more preferable configuration, the transition from ePTFE to PTFE takes place distal to the transition from a flexible helical support to a stiffer helical support as shown in  FIG. 19 . This shows a catheter  1450  with a first liner  1451 , a second liner  1452 , a first helical support  1453 , and a second helical support  1454 . These form a lap joint  1455  and an interwoven region  1456 . This diagram also shows a strike layer  1458 , as described above. 
     In some examples, the first liner is of the same material as the second liner, but having a different thickness. For example, a distal PTFE liner (Liner 1) may be of a lower thickness for enhanced flexibility than the proximal PTFE liner (Liner 2). In another example the liner may be of a different density and/or thickness where both liners are of ePTFE. 
     In  FIG. 19  the plot in the lower part of the figure shows a representative change in stiffness along the catheter from the distal section (left) to the proximal section (right) for the configuration shown. 
     In yet another embodiment, the switch from Liner 1 to Liner 2, and from a flexible helical support to a stiffer helical support takes place at the same location, but within a stiffer jacket material than is present more distally. This has the effect of limiting the deformation which can take place in the area thus limiting the stress and strain locally and protecting the joints. 
     In one embodiment the transition from ePTFE to PTFE liners takes place in a jacket stiffer than 80A polyurethane. Preferably the ePTFE to PTFE transition takes place in a jacket of at least higher stiffness than a more distal jacket, preferably Shore 35D, more preferably Shore 40D, even more preferably Shore 55D, and even more preferably Shore 72D. 
     In one embodiment, the change in helical support types and liner types takes place in a single jacket type as shown in  FIG. 20 . This shows a catheter  1475  with a single jacket body  1471 , and liners and coils as shown in  FIG. 19 . This figure also shows a representative change in stiffness along the catheter from the distal section (left) to the proximal section (right) for the configuration. 
     In another example a change in liner type takes place in a jacket of lower stiffness, at least one pitch of both types of helical support also being present in the jacket of lower stiffness, with the majority of the interwoven region present in a stiffer more proximal jacket as shown in  FIG. 21 . These changes in stiffness may be achieved in a transition portion by varying the durometer of the jacket or altering the thickness. More specifically,  FIG. 21  shows a catheter  1500  having a distal portion with a liner  1501  and a lap joint with a liner  1502 . The lap joint is in the distal portion with a more flexible jacket body  1505  and a first, more flexible, helical support  1503 . The proximal portion has a jacket body  1506  of stiffer material and a stiffer (less flexible) helical support  1504 . The relatively stiff helical support  1504  extends into the distal portion jacket body  1505  in the transition portion. In other examples the coils may overlap only in the distal, or only in the proximal jacket body. 
     This arrangement avoids a sudden step up or down in stiffness. It is preferable to ensure that the joint from one liner type to another is greater than a minimum distance  1507  away from an adjacent jacket of different composition as shown in  FIG. 21 . In one embodiment the distance should be at least 0.2 cm, more preferably at least 0.5 cm, and even more preferably at least 1 cm. 
     In some examples the change from one helical support type to another takes place in a more proximal portion of the catheter which is stiffer than a more flexible portion distally. This provides a more stable matrix for the change in helical support stiffness. This more flexible portion distally may be achieved by use of one or more jackets of progressively increasing stiffness from distal to proximal as shown in  FIG. 22 , distal being on left. This may be termed a transition zone of the catheter. In more detail,  FIG. 22  shows a catheter  1550  distal end with progressively more flexible portions in the distal direction from right to left. There is a jacket body  1551  within which is embedded a lap joint  1557  between two liners  1560  and  1561  and a joint between a proximal coil (helical support)  1558  and a more flexible coil  1559  with wire of smaller diameter. The joint between the coils may simply be the termination of one and start of the other, or they may be physically connected by a connection element as described above, or they may overlap also as described above. The jacket bodies are, in series in the distal direction (right to left)  1552 ,  1551 ,  1553 ,  1554 , and  1555 . There is a separation  1565  between the end of the body  1552  and the start of the distal liner  1561 , and a separation  1566  between the end of the first liner  1560  and the start of the next distal jacket body  1553 . 
     At least one of the more distal jackets may be corrugated for some or all its length. Preferably a more proximal area is not corrugated. Throughout this specification, where a more distal portion is shown un-corrugated, this is merely an example to illustrate another aspect such as a liner or coil joint, and it is to be understood that one or more distal portions are preferably corrugated. Reference is made to  FIGS. 1 to 8  and the accompanying description for details of these aspects. 
       FIG. 22  also shows a representation of reduction in stiffness in the distal direction, which is advantageously smooth, without any sharp transitions. 
     In yet another configuration the joint is present in a region of the catheter which will not be subject to significant bending during use. Therefore, the joint is proximal to the region of the catheter which enters the greatest tortuosity or repeated loading. It is likely to be used in a vessel which is characterized by extreme twists and turns, loop and kinks. In one embodiment the catheter is configured for navigation to the tortuous anatomy of the neurovasculature such as the M1 segment of the middle cerebral artery or distal regions of the internal carotid artery (ICA). In this instance it is preferable to maintain the joint proximal to the petrous bend and more preferably in the proximal part of the ICA. In one embodiment, the joint location is at least 5 cm from the catheter distal end, preferably at least 25 cm from the catheter distal end. 
     Mother and Daughter Catheter Systems 
     Vacuum Transmission 
     Two or more catheters of different sizes above may be used in combination with one another in a mother and daughter configuration. For example, a 6F may be used within an 8F catheter having an inner diameter which accommodates a 6F catheter. 
     A tight fit between the mother and daughter catheter means that application of a vacuum to the proximal end of the mother catheter may not be transferred to the distal end of the mother catheter since the daughter catheter causes an effective seal between the catheters, preventing vacuum transmission from a port on the mother catheter. 
     In some examples the catheters are sized such that there is a gap between the OD of the daughter catheter and the ID of the mother catheter. This means that the physician may apply a vacuum to the distal end of the mother catheter with the daughter catheter in place. This is shown in  FIG. 23 , in which a catheter assembly  1650  has a mother catheter  1651  and a daughter catheter  1652 . There is an annular gap  1653  between the catheters  1652  and  1651  and a vacuum source connected to the hub of the catheter  1654  can apply suction through this gap as illustrated by the arrow in  FIG. 23 . Either or both of the catheters may encompass a corrugated region. 
     Translating one catheter within another in highly tortuous regions can cause the catheters to bind to one another. Maintaining clearance between the ID of one mother catheter and the OD of the daughter catheter reduces the potential for this binding to occur. 
     In various examples the gap has a radial dimension of between 2% and 20% of the ID of the mother catheter, preferably at least 5%, more preferably at least 10%. For example, if the ID of the mother catheter is 2.25 mm (0.088 in), and the outer diameter of the daughter catheter is 2.03 mm (0.080 in), a gap of 0.2 mm (0.008 in) will be present between the catheters, representing a gap in diameter of 9%. 
     In some examples, a gap of at least one-half French size is present between the mother and daughter catheters. In another embodiment a gap of at least one French size is present. 
     In various examples both the mother and daughter catheters are corrugated at the distal ends. While the inner diameter of these portions of the catheter are generally smooth and cylindrical, during bending and manipulation some impression of the corrugations on the inner diameter of the mother catheter may be present. The corrugations of the inner diameter of the mother catheter and outer of the daughter catheter can interact and bind preventing catheter advancement or withdrawal. Such binding may be substantially prevented by the gap as described above. 
     Subtle corrugation may be induced during bending on the inner diameter of the catheters outlined. This is because the presence of corrugations means non-uniform distribution of energy and deformation within the catheter wall. The interaction of these corrugations which occur during bending on the ID of a mother catheter may impede movement of another corrugated catheter (daughter) within the mother catheter. 
     In various examples the pitch of the corrugations is different in the mother catheter to the daughter catheter, reducing potential for corrugations on the ID of the mother catheter and OD of the daughter catheter to nestle within one another, thus preventing bending. The direction of the wind of the corrugations may be different, further reducing potential of the corrugations to snag on one another. 
     Tension Applied to Cinch Wire to Create Corrugation 
     A cinch wire may be used to impart a corrugation pattern onto the OD of the catheter. Depending on the application of use varying tension may be applied to the wire along a length of the catheter to control the depth and or width of corrugation. 
     In particular the profiles may be used in the neurovasculature in conjunction with the embodiments outlined in the tables below. It should be noted that a longer flexible distal catheter section may be preferable on a smaller catheter (e.g. 5 Fr) as it is generally intended to go more distally than a larger catheter. For example, a 5 Fr may be required to go as far as the M3 segment of the middle cerebral artery while an 8 Fr catheter will only required to go as far as the M1 segment of the middle cerebral artery. Intuitively one may expect therefore that more pronounced corrugation should be maintained for a longer distance of the distal catheter length, necessitating a higher force for a longer distance of the distal catheter length. However, at lower diameters for equivalent materials a catheter will be more flexible than its larger brethren. Furthermore, using the embodiments outlined, specifically jackets of durometer 80A-90A with an ePTFE liner, a relatively flexible catheter construction is achieved. Thus, a shorter length of corrugation may be used for smaller catheter diameters while still achieving a suitably flexible and pushable construction. 
     Method of Use of Mother and Daughter Catheter 
     It is a limitation of smaller aspiration catheters that the clot cannot be ingested. The technique in these instances is to cork the clot of the end of the catheter upon application of a vacuum and then to drag the clot out of the body. A known consequence of this technique is fragmentation of the clot during dragging, causing distal emboli. 
     When there is a very small gap present between the mother and daughter catheter to allow transmission of vacuum, this may be insufficient to enable substantial flow and vacuum build-up in the lumen of the mother catheter distal tip. In one embodiment effective transmission of vacuum is achieved by application of the vacuum to the daughter catheter as shown in  FIG. 24 . Arrow A is the vacuum applied to the annular gap and arrow B is that applied to the daughter catheter  1652 . 
     In one method of use the physician uses a daughter aspiration catheter to grab a clot from a distal region of the vasculature,  FIG. 24( a ) . The clot is then brought proximally to the mother catheter tip, or just inside the catheter tip  FIG. 24( b ) . At this point the physician may wish to switch off the vacuum to the daughter catheter, and withdraw the daughter catheter slightly, allowing the mother catheter vacuum to be applied across its entire cross section, maximizing the force holding the clot and the potential for clot ingestion. 
     The daughter catheter  1652  may be further withdrawn such that upon application of a vacuum to the proximal end of the daughter catheter, a vacuum is activated at the distal end of the mother catheter  FIG. 24( c ) . The clot is then grabbed by the vacuum present at the tip of the mother catheter  1651 , increasing the force of aspiration due to the increased lumen surface area. 
     Finally, due to the increased force of aspiration the clot is ingested into the mother catheter  FIG. 24( d ) . This ability to ingest the clot and limit the distance over which it is dragged reduces the potential for distal emboli. 
       FIG. 25  is a diagram showing transitions between catheter portions in a direction from proximal (left) and distal (right) in one example catheter  1800  having some of the features illustrated in the other drawings. 
     This illustrates in one diagram a number of the advantageous features of catheters of the invention, and some of these features may be employed without others in any catheter encompassed by the invention. For example, there may be a lap joint portion akin to  1804  but within a jacket with corrugations, and/or not adjacent a portion with interwoven coils. 
     The regions are set out in Table 2: 
     
       
         
           
               
               
               
             
               
                   
                   
               
             
            
               
                   
                 1801 
                 Hub 
               
               
                   
                 1802 
                 Proximal support (also referred to as  
               
               
                   
                   
                 radial support or helical support or coil) 
               
               
                   
                 1803 
                 Interwoven Supports 
               
               
                   
                 1804 
                 Liner Lap Joint between a proximal liner  
               
               
                   
                   
                 and a distal liner of more flexibility 
               
               
                   
                 1805 
                 End of jacket material body which has a  
               
               
                   
                   
                 greater depth or stiffness, with a small  
               
               
                   
                   
                 step-down in depth or stiffness to the  
               
               
                   
                   
                 next more distal portion. 
               
               
                   
                 1806 
                 Jacket body which is still un-corrugated  
               
               
                   
                   
                 but has less depth or stiffness than the  
               
               
                   
                   
                 of the portion 1805 and more proximally 
               
               
                   
                 1807 
                 Change to increase in coil pitch,  
               
               
                   
                   
                 reduction in jacket stiffness 
               
               
                   
                 1808 
                 Shallow corrugations and width 
               
               
                   
                 1809 
                 Increasing corrugation depth and width 
               
               
                   
                 1810 
                 Further increase in corrugation depth 
               
               
                   
                 1811 
                 Distal Support (also referred to as radial  
               
               
                   
                   
                 support or helical support) 
               
               
                   
                 1812 
                 Marker Band 
               
               
                   
                 1813 
                 Atrumatic Tip 
               
               
                   
                 1814 
                 Distal end of the distal liner 
               
               
                   
                   
               
            
           
         
       
     
     Table 2, features in order towards the distal tip of a catheter, such features being advantageous when combined as some or all of the features in this table. 
     Any or all of these features may be present in a daughter or a mother catheter. 
     Preferred Configurations and Dimensions of Corrugated Catheters 
     Preferred attributes and catheter dimensions are outlined for a range of catheter sizes are outlined in Table 3 to Table 8. The dimensions shown represent a catheter without a hydrophilic coating. A reference configuration and associated parameters are shown in  FIG. 2 . 
     In one embodiment there is a reduction in the pitch of the distal helical support (coil pitch) within the un-corrugated area of the most distal jacket just proximal to the start of a stiffer and more proximal jacket. This reduction in pitch serves limit the sudden change in stiffness due to the change in jacket material. 
     
       
         
           
               
             
               
                 TABLE 3 
               
             
            
               
                   
               
               
                 Preferred attributes for catheters with a  
               
               
                 flexible corrugated tip for intravascular use. 
               
            
           
           
               
               
               
               
            
               
                   
                 Attribute 
                 Preferable 
                 More Preferable 
               
               
                   
                   
               
               
                   
                 Variance in depth  
                 Variable along  
                 Variable along  
               
               
                   
                 of corrugation 
                 length (increasing  
                 length (increasing  
               
               
                   
                   
                 distally) 
                 distally) 
               
               
                   
                 Variance in width  
                 Variable along  
                 No variable 
               
               
                   
                 of corrugation 
                 length (increasing  
                   
               
               
                   
                   
                 distally) 
                   
               
               
                   
                 Recess Geometry 
                 Round, U, V,  
                 U 
               
               
                   
                   
                 Square 
                   
               
               
                   
                 Rib Geometry 
                 Avoid square  
                 Rounded edge,  
               
               
                   
                   
                 profile 
                 or inverted U 
               
               
                   
                 Distal Liner  
                 PTFE or expanded  
                 ePTFE 
               
               
                   
                 Material 
                 PTFE (Fibrous and  
                   
               
               
                   
                   
                 compressible) 
                   
               
               
                   
                 Distal Liner  
                 Radially Stretched 
                 Radially stretched,  
               
               
                   
                 Condition on  
                   
                 Axially Compressed 
               
               
                   
                 Mandrel Distal 
                   
                   
               
               
                   
                 Section of Tip 
                   
                   
               
               
                   
                 Distal Liner  
                 Radially Stretched 
                 Radially Stretched,  
               
               
                   
                 Condition on  
                   
                 Axially Stretched 
               
               
                   
                 Mandrel Proximal 
                   
                   
               
               
                   
                 Section of Tip 
                   
                   
               
               
                   
                 Proximal Liner  
                 ePTFE or PTFE  
                 PTFE with Strike  
               
               
                   
                 Material 
                 or HDPE or  
                 Layer 
               
               
                   
                   
                 Polyamide 
                   
               
               
                   
                 Proximal Liner  
                 None or TPU or  
                 Polyether block  
               
               
                   
                 Strike Layer 
                 Polyether block  
                 amide 52D or  
               
               
                   
                   
                 amide 
                 35D, more ideally  
               
               
                   
                   
                   
                 aligned with jacket  
               
               
                   
                   
                   
                 outside liner 
               
               
                   
                 Distal helical  
                 Nitinol or stainless  
                 Superelastic  
               
               
                   
                 Support Material 
                 steel or cobalt  
                 Nitinol 
               
               
                   
                   
                 chromium or  
                   
               
               
                   
                   
                 nlyon, or PET or  
                   
               
               
                   
                   
                 other polymer 
                   
               
               
                   
                 Proximal Support 
                 Nitinol or stainless  
                 Stainless steel 
               
               
                   
                 Material 
                 steel or cobalt  
                   
               
               
                   
                   
                 chromium or  
                   
               
               
                   
                   
                 nlyon, or PET or  
                   
               
               
                   
                   
                 other polymer 
                   
               
               
                   
                 Location of  
                 Within 80A  
                 Within distal  
               
               
                   
                 Corrugated Section 
                 section 
                 area of 80A  
               
               
                   
                   
                   
                 section, proximal  
               
               
                   
                   
                   
                 to marker band 
               
               
                   
                 Location of ePTFE  
                 Proximal to  
                 Within 72D or  
               
               
                   
                 and PTFE Joint 
                 80A section 
                 stiffest polymer  
               
               
                   
                   
                   
                 jacket 
               
               
                   
                 Location of ePTFE  
                 Proximal to  
                 Proximal to 80A  
               
               
                   
                 and PTFE Joint if 
                 corrugated 80A  
                 Section, distal to  
               
               
                   
                 configuration  
                 section 
                 transition from distal  
               
               
                   
                 contains different  
                   
                 helical support to  
               
               
                   
                 helical supports  
                   
                 proximal helical  
               
               
                   
                 distally and  
                   
                 support and within  
               
               
                   
                 proximally 
                   
                 stiffest polymer  
               
               
                   
                   
                   
                 jacket 
               
               
                   
                 Type of Joint of  
                 Overlap or Butt 
                 Overlap/Lap 
               
               
                   
                 ePTFE and PTFE 
                   
                   
               
               
                   
                 Distal Jacket  
                 TPU or Pebax 
                 90A or 80A TPU 
               
               
                   
                 Material 
                   
                   
               
               
                   
                 Proximal Jacket  
                 High Durometer 
                 Polyether Block  
               
               
                   
                 Material 
                 Thermoplastic 
                 Amide 55D to 75D 
               
               
                   
                 Cinch Wire Shape 
                 Round, Square,  
                 Round 
               
               
                   
                   
                 or Angled 
               
               
                   
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 4 
               
             
            
               
                   
               
               
                 Preferred Attributes for a 5F Corrugated Catheter 
               
            
           
           
               
               
               
               
            
               
                 5F Corrugated Catheter 
                   
                 Range 
                 Preferable 
               
            
           
           
               
               
               
               
               
               
            
               
                 Attribute 
                 Symbol 
                 Min 
                 Max 
                 Min 
                 Max 
               
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Catheter Outer Diameter (mm) 
                 OD 
                 1.44 
                 1.70 
                 1.61 
                 1.70 
               
               
                 Catheter Inner Diameter (mm) 
                 ID 
                 1.06 
                 1.55 
                 1.34 
                 1.53 
               
               
                 Distal Corrugation Depth (mm) 
                 d corr distal   
                 0.016 
                 0.138 
                 0.050 
                 0.125 
               
               
                 Distal Residual Depth (mm) 
                 d res   
                 0.016 
                 0.094 
                 0.031 
                 0.063 
               
               
                 Distal Corrugation Width (mm) 
                 W 
                 0.016 
                 0.156 
                 0.094 
                 0.150 
               
               
                 Rib fillet radius (mm) 
                 r rib   
                 0.008 
                 0.156 
                 0.031 
                 0.094 
               
               
                 Length of Corrugated Section (cm) 
                 L cor   
                 6 
                 18 
                 7 
                 12 
               
               
                 Length of Proximal Uncorrugated  
                 L uncor   
                 1 
                 10 
                 4 
                 6 
               
               
                 Section of Distal Jacket Material (cm) 
                   
                   
                   
                   
                   
               
               
                 Distal Liner Density (g/cm 3 ) 
                 — 
                 0.4 
                 1.2 
                 0.4 
                 0.6 
               
               
                 Distal Liner Thickness pre-assembly (mm) 
                 t distal liner   
                 0.015 
                 0.102 
                 0.016 
                 0.048 
               
               
                 Distal Liner % Radial Stretch (%) 
                 — 
                 5 
                 25 
                 18 
                 24 
               
               
                 Proximal Liner ID (mm) 
                 — 
                 1.12 
                 1.63 
                 1.40 
                 1.61 
               
               
                 Proximal Liner wall thickness (mm) 
                 t proximal liner   
                 0.013 
                 0.050 
                 0.013 
                 0.019 
               
               
                 Atraumatic Tip Length 
                 — 
                 0.31 
                 1.25 
                 0.63 
                 0.78 
               
               
                 (Uncoiled section 80A length distal  
                   
                   
                   
                   
                   
               
               
                 to radiopaque marker band) (mm) 
                   
                   
                   
                   
                   
               
               
                 Distal Helical Support Diameter (mm) 
                 ID Support    
                 1.19 
                 1.50 
                 1.31 
                 1.44 
               
               
                   
                 Distal 
                   
                   
                   
                   
               
               
                 Distal Support Wire Diameter (mm) 
                 D coil  Distal 
                 0.048 
                 0.125 
                 0.056 
                 0.069 
               
               
                 Proximal Helical Support Diameter (mm) 
                 ID Support    
                 1.19 
                 1.50 
                 1.31 
                 1.44 
               
               
                   
                 Proximal 
                   
                   
                   
                   
               
               
                 Proximal Helical Wire Diameter (mm) 
                 D coil    
                 0.069 
                 0.125 
                 0.084 
                 0.109 
               
               
                   
                 Proximal 
                   
                   
                   
                   
               
               
                 Distance of ePTFE and PTFE Joint  
                 — 
                 2 
                 20 
                 5 
                 15 
               
               
                 from transition from adjacent jacket  
                   
                   
                   
                   
                   
               
               
                 of a different stiffness/diameter (mm) 
                   
                   
                   
                   
                   
               
               
                 Length of Lap Joint (mm) 
                 — 
                 3.1 
                 18.8 
                 5.6 
                 6.9 
               
               
                 Length of Radial Support 
                 — 
                 0.2 
                 12.5 
                 5.6 
                 6.9 
               
               
                 Overlap (mm) 
                   
                   
                   
                   
                   
               
               
                 Number of interwoven pitches in radial  
                 — 
                 1 
                 28 
                 12 
                 14 
               
               
                 support overlap 
                   
                   
                   
                   
                   
               
               
                 Corrugation Pitch (mm) 
                 Corrugation  
                 0.06 
                 0.47 
                 0.25 
                 0.31 
               
               
                 Distal Support Pitch (mm) 
                 Pitch  Distal   
                   
                   
                   
                   
               
               
                 Proximal Support Pitch (mm) 
                 Corrugation  
                 0.06 
                 0.47 
                 0.19 
                 0.25 
               
               
                   
                 Pitch  Proximal   
                   
                   
                   
                   
               
               
                 Cinch Wire Diameter (mm) 
                 — 
                 0.031 
                 0.250 
                 0.119 
                 0.131 
               
               
                 Winding Tension Applied to Cinch Wire  
                 — 
                 1 
                 25 
                 4 
                 8 
               
               
                 at Distal End (N) 
                   
                   
                   
                   
                   
               
               
                 Winding Tension Applied to Cinch Wire  
                 — 
                 0 
                 25 
                 0 
                 1 
               
               
                 at Proximal End (N) 
                   
                   
                   
                   
                   
               
               
                 Distal Jacket ID Pre Lamination (mm) 
                 — 
                 1.56 
                 2.38 
                 1.66 
                 1.84 
               
               
                 Distal Jacket Wall thickness Pre- 
                 — 
                 0.048 
                 0.095 
                 0.063 
                 0.079 
               
               
                 Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Proximal Jacket ID Pre Lamination (mm) 
                 — 
                 1.56 
                 2.19 
                 1.66 
                 1.84 
               
               
                 Proximal Jacket Wall Thickness Pre- 
                 — 
                 0.063 
                 0.125 
                 0.088 
                 0.113 
               
               
                 Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Volume of Proximal Jacket Per Unit  
                   
                 0.32 
                 0.91 
                 0.48 
                 0.69 
               
               
                 Catheter Length (mm 2 /F) 
                   
                   
                   
                   
                   
               
               
                 Volume of Distal Jacket Per Unit Catheter  
                   
                 0.24 
                 0.74 
                 0.34 
                 0.48 
               
               
                 Length (mm 2 /F) 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 5 
               
             
            
               
                   
               
               
                 Preferred Attributes for a 6F Corrugated Catheter 
               
            
           
           
               
               
               
               
            
               
                 6F Corrugated Catheter 
                   
                 Range 
                 Preferable 
               
            
           
           
               
               
               
               
               
               
            
               
                 Attribute 
                 Symbol 
                 Min 
                 Max 
                 Min 
                 Max 
               
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Catheter Outer Diameter (mm) 
                 OD 
                 1.73 
                 2.03 
                 1.95 
                 2.03 
               
               
                 Catheter Inner Diameter (mm) 
                 ID 
                 1.65 
                 1.90 
                 1.72 
                 1.85 
               
               
                 Distal Corrugation Depth (mm) 
                 d corr distal   
                 0.019 
                 0.165 
                 0.060 
                 0.15 
               
               
                 Distal Residual Depth (mm) 
                 d res   
                 0.019 
                 0.113 
                 0.038 
                 0.08 
               
               
                 Distal Corrugation Width (mm) 
                 W 
                 0.019 
                 0.188 
                 0.113 
                 0.18 
               
               
                 Rib fillet radius (mm) 
                 r rib   
                 0.009 
                 0.188 
                 0.038 
                 0.113 
               
               
                 Length of Corrugated Section (cm) 
                 L cor   
                 5 
                 17 
                 7 
                 12 
               
               
                 Length of Proximal Uncorrugated  
                 L uncor   
                 1 
                 10 
                 4 
                 6 
               
               
                 Section of Distal Jacket Material (cm) 
                   
                   
                   
                   
                   
               
               
                 Distal Liner Density (g/cm 3 ) 
                 — 
                 0.4 
                 1.2 
                 0.4 
                 0.6 
               
               
                 Distal Liner Thickness pre-assembly (mm) 
                 t distal liner   
                 0.015 
                 0.102 
                 0.019 
                 0.057 
               
               
                 Distal Liner % Radial Stretch (%) 
                 — 
                 5 
                 25 
                 18 
                 24 
               
               
                 Proximal Liner ID (mm) 
                 — 
                 1.73 
                 2.00 
                 1.81 
                 1.94 
               
               
                 Proximal Liner wall thickness (mm) 
                 t proximal liner   
                 0.013 
                 0.050 
                 0.015 
                 0.023 
               
               
                 Atraumatic Tip Length 
                 — 
                 0.38 
                 1.50 
                 0.75 
                 0.94 
               
               
                 (Uncoiled section 80A length distal  
                   
                   
                   
                   
                   
               
               
                 to radiopaque marker band) (mm) 
                   
                   
                   
                   
                   
               
               
                 Distal Helical Support Diameter (mm) 
                 ID Support    
                 1.43 
                 1.80 
                 1.58 
                 1.73 
               
               
                   
                 Distal 
                   
                   
                   
                   
               
               
                 Distal Support Wire Diameter (mm) 
                 D coil  Distal 
                 0.057 
                 0.150 
                 0.068 
                 0.083 
               
               
                 Proximal Helical Support Diameter (mm) 
                 ID Support    
                 1.43 
                 1.80 
                 1.58 
                 1.73 
               
               
                   
                 Proximal 
                   
                   
                   
                   
               
               
                 Proximal Helical Wire Diameter (mm) 
                 D coil    
                 0.083 
                 0.150 
                 0.101 
                 0.131 
               
               
                   
                 Proximal 
                   
                   
                   
                   
               
               
                 Distance of ePTFE and PTFE Joint  
                 — 
                 2 
                 20 
                 5 
                 15 
               
               
                 from transition from adjacent jacket  
                   
                   
                   
                   
                   
               
               
                 of a different stiffness/diameter (mm) 
                   
                   
                   
                   
                   
               
               
                 Length of Lap Joint (mm) 
                 — 
                 3.8 
                 22.5 
                 6.8 
                 8.3 
               
               
                 Length of Radial Support Overlap (mm) 
                 — 
                 0.3 
                 15.0 
                 6.8 
                 8.3 
               
               
                 Number of interwoven pitches in radial  
                 — 
                 1 
                 28 
                 12 
                 14 
               
               
                 support overlap 
                   
                   
                   
                   
                   
               
               
                 Corrugation Pitch (mm) 
                 Corrugation  
                 0.08 
                 0.56 
                 0.30 
                 0.38 
               
               
                 Distal Support Pitch (mm) 
                 Pitch  Distal   
                   
                   
                   
                   
               
               
                 Proximal Support Pitch (mm) 
                 Corrugation  
                 0.08 
                 0.56 
                 0.23 
                 0.30 
               
               
                   
                 Pitch  Proximal   
                   
                   
                   
                   
               
               
                 Cinch Wire Diameter (mm) 
                   
                 0.038 
                 0.300 
                 0.143 
                 0.158 
               
               
                 Winding Tension Applied to Cinch Wire  
                 — 
                 1 
                 25 
                 6 
                 10 
               
               
                 at Distal End (N) 
                   
                   
                   
                   
                   
               
               
                 Winding Tension Applied to Cinch Wire  
                 — 
                 0 
                 25 
                 0 
                 1 
               
               
                 at Proximal End (N) 
                   
                   
                   
                   
                   
               
               
                 Distal Jacket ID Pre Lamination (mm) 
                 — 
                 1.88 
                 2.85 
                 1.99 
                 2.21 
               
               
                 Distal Jacket Wall thickness Pre- 
                 — 
                 0.057 
                 0.114 
                 0.076 
                 0.095 
               
               
                 Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Proximal Jacket ID Pre Lamination (mm) 
                 — 
                 1.88 
                 2.63 
                 1.99 
                 2.21 
               
               
                 Proximal Jacket Wall Thickness Pre- 
                 — 
                 0.075 
                 0.150 
                 0.105 
                 0.135 
               
               
                 Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Volume of Proximal Jacket Per Unit  
                   
                 0.46 
                 1.31 
                 0.69 
                 1.00 
               
               
                 Catheter Length (mm 2 /F) 
                   
                   
                   
                   
                   
               
               
                 Volume of Distal Jacket Per Unit Catheter  
                   
                 0.35 
                 1.06 
                 0.49 
                 0.69 
               
               
                 Length (mm 2 /F) 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 6 
               
             
            
               
                   
               
               
                 Preferred Attributes for a 7F Corrugated Catheter 
               
            
           
           
               
               
               
               
            
               
                 7F Corrugated Catheter 
                   
                 Range 
                 Preferable 
               
            
           
           
               
               
               
               
               
               
            
               
                 Attribute 
                 Symbol 
                 Min 
                 Max 
                 Min 
                 Max 
               
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Catheter Outer Diameter (mm) 
                 OD 
                 2.01 
                 2.36 
                 2.28 
                 2.36 
               
               
                 Catheter Inner Diameter (mm) 
                 ID 
                 1.49 
                 2.10 
                 1.87 
                 2.05 
               
               
                 Distal Corrugation Depth (mm) 
                 d corr distal   
                 0.022 
                 0.193 
                 0.070 
                 0.175 
               
               
                 Distal Residual Depth (mm) 
                 d res   
                 0.022 
                 0.131 
                 0.044 
                 0.088 
               
               
                 Distal Corrugation Width (mm) 
                 W 
                 0.022 
                 0.219 
                 0.131 
                 0.210 
               
               
                 Rib fillet radius (mm) 
                 r rib   
                 0.011 
                 0.219 
                 0.044 
                 0.131 
               
               
                 Length of Corrugated Section (cm) 
                 L cor   
                 4 
                 16 
                 10 
                 14 
               
               
                 Length of Proximal Uncorrugated  
                 L uncor   
                 1 
                 10 
                 4 
                 6 
               
               
                 Section of Distal Jacket Material (cm) 
                   
                   
                   
                   
                   
               
               
                 Distal Liner Density (g/cm 3 ) 
                 — 
                 0.4 
                 1.2 
                 0.4 
                 0.6 
               
               
                 Distal Liner Thickness pre-assembly (mm) 
                 t distal liner   
                 0.015 
                 0.102 
                 0.022 
                 0.067 
               
               
                 Distal Liner % Radial Stretch (%) 
                 — 
                 5 
                 25 
                 18 
                 24 
               
               
                 Proximal Liner ID (mm) 
                 — 
                 1.56 
                 2.21 
                 1.97 
                 2.15 
               
               
                 Proximal Liner wall thickness (mm) 
                 t proximal liner   
                 0.013 
                 0.050 
                 0.018 
                 0.026 
               
               
                 Atraumatic Tip Length 
                 — 
                 0.44 
                 1.75 
                 0.88 
                 1.09 
               
               
                 (Uncoiled section 80A length distal  
                   
                   
                   
                   
                   
               
               
                 to radiopaque marker band) (mm) 
                   
                   
                   
                   
                   
               
               
                 Distal Helical Support Diameter (mm) 
                 ID Support    
                 1.66 
                 2.10 
                 1.84 
                 2.01 
               
               
                   
                 Distal 
                   
                   
                   
                   
               
               
                 Distal Support Wire Diameter (mm) 
                 D coil  Distal 
                 0.067 
                 0.175 
                 0.079 
                 0.096 
               
               
                 Proximal Helical Support Diameter (mm) 
                 ID Support    
                 1.66 
                 2.10 
                 1.84 
                 2.01 
               
               
                   
                 Proximal 
                   
                   
                   
                   
               
               
                 Proximal Helical Wire Diameter (mm) 
                 D coil    
                 0.096 
                 0.175 
                 0.118 
                 0.153 
               
               
                   
                 Proximal 
                   
                   
                   
                   
               
               
                 Distance of ePTFE and PTFE Joint  
                 — 
                 2 
                 20 
                 5 
                 15 
               
               
                 from transition from adjacent jacket  
                   
                   
                   
                   
                   
               
               
                 of a different stiffness/diameter (mm) 
                   
                   
                   
                   
                   
               
               
                 Length of Lap Joint (mm) 
                 — 
                 4.4 
                 26.3 
                 7.9 
                 9.6 
               
               
                 Length of Radial Support Overlap (mm) 
                 — 
                 0.3 
                 17.5 
                 7.9 
                 9.6 
               
               
                 Number of interwoven pitches in radial  
                 — 
                 1 
                 28 
                 12 
                 14 
               
               
                 support overlap 
                   
                   
                   
                   
                   
               
               
                 Corrugation Pitch (mm) 
                 Corrugation  
                 0.09 
                 0.66 
                 0.35 
                 0.44 
               
               
                 Distal Support Pitch (mm) 
                 Pitch  Distal   
                   
                   
                   
                   
               
               
                 Proximal Support Pitch (mm) 
                 Corrugation  
                 0.09 
                 0.66 
                 0.26 
                 0.35 
               
               
                   
                 Pitch  Proximal   
                   
                   
                   
                   
               
               
                 Cinch Wire Diameter (mm) 
                 — 
                 0.044 
                 0.350 
                 0.166 
                 0.184 
               
               
                 Winding Tension Applied to Cinch Wire  
                 — 
                 1 
                 25 
                 8 
                 12 
               
               
                 at Distal End (N) 
                   
                   
                   
                   
                   
               
               
                 Winding Tension Applied to Cinch Wire  
                 — 
                 0 
                 25 
                 0 
                 1 
               
               
                 at Proximal End (N) 
                   
                   
                   
                   
                   
               
               
                 Distal Jacket ID Pre Lamination (mm) 
                 — 
                 2.19 
                 3.33 
                 2.32 
                 2.58 
               
               
                 Distal Jacket Wall thickness Pre- 
                 — 
                 0.067 
                 0.133 
                 0.088 
                 0.111 
               
               
                 Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Proximal Jacket ID Pre Lamination (mm) 
                 — 
                 2.19 
                 3.06 
                 2.32 
                 2.58 
               
               
                 Proximal Jacket Wall Thickness Pre- 
                 — 
                 0.088 
                 0.175 
                 0.123 
                 0.158 
               
               
                 Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Volume of Proximal Jacket Per Unit  
                   
                 0.63 
                 1.78 
                 0.94 
                 1.36 
               
               
                 Catheter Length (mm 2 /F) 
                   
                   
                   
                   
                   
               
               
                 Volume of Distal Jacket Per Unit Catheter  
                   
                 0.47 
                 1.44 
                 0.67 
                 0.94 
               
               
                 Length (mm 2 /F) 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 7 
               
             
            
               
                   
               
               
                 Preferred Attributes for an 8F Corrugated Catheter 
               
            
           
           
               
               
               
               
            
               
                 8F Corrugated Catheter 
                   
                 Range 
                 Preferable Range 
               
            
           
           
               
               
               
               
               
               
            
               
                 Attribute 
                 Symbol 
                 Min 
                 Max 
                 Min 
                 Max 
               
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Catheter Outer Diameter (mm) 
                 OD 
                 2.30 
                 2.70 
                 2.60 
                 2.70 
               
               
                 Catheter Inner Diameter (mm) 
                 ID 
                 1.70 
                 2.40 
                 2.14 
                 2.34 
               
               
                 Distal Corrugation Depth (mm) 
                 d corr distal   
                 0.025 
                 0.220 
                 0.080 
                 0.200 
               
               
                 Distal Residual Depth (mm) 
                 d res   
                 0.025 
                 0.150 
                 0.050 
                 0.100 
               
               
                 Distal Corrugation Width (mm) 
                 W 
                 0.025 
                 0.250 
                 0.150 
                 0.240 
               
               
                 Rib fillet radius (mm) 
                 r rib   
                 0.012 
                 0.250 
                 0.050 
                 0.150 
               
               
                 Length of Corrugated Section 
                 L cor   
                 4 
                 15 
                 12 
                 14 
               
               
                 (cm) 
                   
                   
                   
                   
                   
               
               
                 Length of Proximal 
                 L uncor   
                 1 
                 8 
                 3 
                 5 
               
               
                 Uncorrugated Section of Distal 
                   
                   
                   
                   
                   
               
               
                 Jacket Material (cm) 
                   
                   
                   
                   
                   
               
               
                 Distal Liner Density (g/cm 3 ) 
                 — 
                 0.4 
                 1.2 
                 0.4 
                 0.6 
               
               
                 Distal Liner Thickness pre-  
                 t distal liner   
                 0.015 
                 0.102 
                 0.025 
                 0.076 
               
               
                 assembly (mm) 
                   
                   
                   
                   
                   
               
               
                 Distal Liner % Radial Stretch 
                 — 
                 5 
                 25 
                 20 
                 22 
               
               
                 (%) 
                   
                   
                   
                   
                   
               
               
                 Proximal Liner ID (mm) 
                 — 
                 1.79 
                 2.52 
                 2.20 
                 2.40 
               
               
                 Proximal Liner wall thickness 
                 t proximal liner   
                 0.013 
                 0.050 
                 0.020 
                 0.030 
               
               
                 (mm) 
                   
                   
                   
                   
                   
               
               
                 Atraumatic Tip Length 
                 — 
                 0.50 
                 2.00 
                 1.00 
                 1.25 
               
               
                 (Uncoiled section 80A length 
                   
                   
                   
                   
                   
               
               
                 distal to radiopaque marker 
                   
                   
                   
                   
                   
               
               
                 band) (mm) 
                   
                   
                   
                   
                   
               
               
                 Distal Helical Support 
                 ID Support    
                 1.90 
                 2.40 
                 2.10 
                 2.30 
               
               
                 Diameter (mm) 
                 Distal 
                   
                   
                   
                   
               
               
                 Distal Support Wire Diameter 
                 D coil  Distal 
                 0.076 
                 0.200 
                 0.090 
                 0.110 
               
               
                 (mm) 
                   
                   
                   
                   
                   
               
               
                 Proximal Helical Support 
                 ID Support    
                 1.90 
                 2.40 
                 2.10 
                 2.30 
               
               
                 Diameter (mm) 
                 Proximal 
                   
                   
                   
                   
               
               
                 Proximal Helical Wire 
                 D coil    
                 0.110 
                 0.200 
                 0.135 
                 0.175 
               
               
                 Diameter (mm) 
                 Proximal 
                   
                   
                   
                   
               
               
                 Distance of ePTFE and PTFE 
                 — 
                 2 
                 20 
                 5 
                 15 
               
               
                 Joint from transition from 
                   
                   
                   
                   
                   
               
               
                 adjacent jacket of a different 
                   
                   
                   
                   
                   
               
               
                 stiffness/diameter (mm) 
                   
                   
                   
                   
                   
               
               
                 Length of Lap Joint (mm) 
                 — 
                 5.0 
                 30.0 
                 9.0 
                 11.0 
               
               
                 Length of Radial Support 
                 — 
                 0.4 
                 20.0 
                 9.0 
                 11.0 
               
               
                 Overlap (mm) 
                   
                   
                   
                   
                   
               
               
                 Number of interwoven pitches 
                 — 
                 1 
                 28 
                 12 
                 14 
               
               
                 in radial support overlap 
                   
                   
                   
                   
                   
               
               
                 Corrugation Pitch (mm) Distal 
                 Corrugation  
                 0.10 
                 0.75 
                 0.40 
                 0.50 
               
               
                 Support Pitch (mm)  
                 Pitch  Distal   
                   
                   
                   
                   
               
               
                 Proximal Support Pitch (mm) 
                 Corrugation  
                 0.10 
                 0.75 
                 0.30 
                 0.40 
               
               
                   
                 Pitch  Proximal   
                   
                   
                   
                   
               
               
                 Cinch Wire Diameter (mm) 
                 — 
                 0.050 
                 0.400 
                 0.190 
                 0.210 
               
               
                 Winding Tension Applied to 
                 — 
                 1 
                 25 
                 11 
                 14 
               
               
                 Cinch Wire at Distal End (N) 
                   
                   
                   
                   
                   
               
               
                 Winding Tension Applied to 
                 — 
                 0 
                 25 
                 0 
                 1 
               
               
                 Cinch Wire at Proximal End (N) 
                   
                   
                   
                   
                   
               
               
                 Distal Jacket ID Pre Lamination 
                 — 
                 2.50 
                 3.80 
                 2.65 
                 2.95 
               
               
                 (mm) 
                   
                   
                   
                   
                   
               
               
                 Distal Jacket Wall thickness 
                 — 
                 0.076 
                 0.152 
                 0.101 
                 0.127 
               
               
                 Pre-Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Proximal Jacket ID Pre 
                 — 
                 2.50 
                 3.50 
                 2.65 
                 2.95 
               
               
                 Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Proximal Jacket Wall Thickness 
                 — 
                 0.100 
                 0.200 
                 0.140 
                 0.180 
               
               
                 Pre-Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Volume of Proximal Jacket Per 
                   
                 0.82 
                 2.32 
                 1.23 
                 1.77 
               
               
                 Unit Catheter Length (mm 2 /F) 
                   
                   
                   
                   
                   
               
               
                 Volume of Distal Jacket Per  
                   
                 0.62 
                 1.89 
                 0.87 
                 1.23 
               
               
                 Unit Catheter Length (mm 2 /F) 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 8 
               
             
            
               
                   
               
               
                 Preferred Attributes for a 9F Corrugated Catheter 
               
            
           
           
               
               
               
               
            
               
                 9F Corrugated Catheter 
                   
                 Range 
                 Preferable 
               
            
           
           
               
               
               
               
               
               
            
               
                 Attribute 
                 Symbol 
                 Min 
                 Max 
                 Min 
                 Max 
               
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Catheter Outer Diameter (mm) 
                 OD 
                 2.59 
                 3.04 
                 2.93 
                 3.04 
               
               
                 Catheter Inner Diameter (mm) 
                 ID 
                 1.91 
                 2.72 
                 2.41 
                 2.71 
               
               
                 Distal Corrugation Depth (mm) 
                 d corr distal   
                 0.028 
                 0.248 
                 0.090 
                 0.225 
               
               
                 Distal Residual Depth (mm) 
                 d res   
                 0.028 
                 0.169 
                 0.056 
                 0.113 
               
               
                 Distal Corrugation Width (mm) 
                 W 
                 0.028 
                 0.281 
                 0.169 
                 0.270 
               
               
                 Rib fillet radius (mm) 
                 r rib   
                 0.014 
                 0.281 
                 0.056 
                 0.169 
               
               
                 Length of Corrugated Section (cm) 
                 L cor   
                 8 
                 17 
                 10 
                 16 
               
               
                 Length of Proximal Uncorrugated  
                 L uncor   
                 1 
                 10 
                 4 
                 6 
               
               
                 Section of Distal Jacket Material (cm) 
                   
                   
                   
                   
                   
               
               
                 Distal Liner Density (g/cm 3 ) 
                 — 
                 0.4 
                 1.2 
                 0.4 
                 0.6 
               
               
                 Distal Liner Thickness pre-assembly (mm)  
                 t distal liner   
                 0.015 
                 0.102 
                 0.028 
                 0.086 
               
               
                 Distal Liner % Radial Stretch (%) 
                 — 
                 5 
                 25 
                 18 
                 24 
               
               
                 Proximal Liner ID (mm) 
                 — 
                 2.01 
                 2.84 
                 2.48 
                 2.70 
               
               
                 Proximal Liner wall thickness (mm) 
                 t proximal liner   
                 0.013 
                 0.050 
                 0.023 
                 0.034 
               
               
                 Atraumatic Tip Length 
                 — 
                 0.56 
                 2.25 
                 1.13 
                 1.41 
               
               
                 (Uncoiled section 80A length distal  
                   
                   
                   
                   
                   
               
               
                 to radiopaque marker band) (mm) 
                   
                   
                   
                   
                   
               
               
                 Distal Helical Support Diameter (mm) 
                 ID support    
                 2.14 
                 2.70 
                 2.36 
                 2.59 
               
               
                   
                 Distal 
                   
                   
                   
                   
               
               
                 Distal Support Wire Diameter (mm) 
                 D coil  Distal 
                 0.086 
                 0.225 
                 0.101 
                 0.124 
               
               
                 Proximal Helical Support Diameter (mm) 
                 ID support    
                 2.14 
                 2.70 
                 2.36 
                 2.59 
               
               
                   
                 Proximal 
                   
                   
                   
                   
               
               
                 Proximal Helical Wire Diameter (mm) 
                 D coil    
                 0.124 
                 0.225 
                 0.152 
                 0.197 
               
               
                   
                 Proximal 
                   
                   
                   
                   
               
               
                 Distance of ePTFE and PTFE Joint  
                 — 
                 2 
                 20 
                 5 
                 15 
               
               
                 from transition from adjacent jacket  
                   
                   
                   
                   
                   
               
               
                 of a different stiffness/diameter (mm) 
                   
                   
                   
                   
                   
               
               
                 Length of Lap Joint (mm) 
                 — 
                 5.6 
                 33.8 
                 10.1 
                 12.4 
               
               
                 Length of Radial Support Overlap (mm) 
                 — 
                 0.4 
                 22.5 
                 10.1 
                 12.4 
               
               
                 Number of interwoven pitches in radial  
                 — 
                 1 
                 28 
                 12 
                 14 
               
               
                 support overlap 
                   
                   
                   
                   
                   
               
               
                 Corrugation Pitch (mm) 
                 Corrugation  
                 0.11 
                 0.84 
                 0.45 
                 0.56 
               
               
                 Distal Support Pitch (mm) 
                 Pitch  Distal   
                   
                   
                   
                   
               
               
                 Proximal Support Pitch (mm) 
                 Corrugation  
                 0.11 
                 0.84 
                 0.34 
                 0.45 
               
               
                   
                 Pitch  Proximal   
                   
                   
                   
                   
               
               
                 Cinch Wire Diameter (mm) 
                 — 
                 0.056 
                 0.450 
                 0.214 
                 0.236 
               
               
                 Winding Tension Applied to Cinch Wire  
                 — 
                 1 
                 25 
                 12 
                 16 
               
               
                 at Distal End (N) 
                   
                   
                   
                   
                   
               
               
                 Winding Tension Applied to Cinch Wire  
                 — 
                 0 
                 25 
                 0 
                 1 
               
               
                 at Proximal End (N) 
                   
                   
                   
                   
                   
               
               
                 Distal Jacket ID Pre Lamination (mm) 
                 — 
                 2.81 
                 4.28 
                 2.98 
                 3.32 
               
               
                 Distal Jacket Wall thickness Pre- 
                 — 
                 0.086 
                 0.171 
                 0.114 
                 0.143 
               
               
                 Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Proximal Jacket ID Pre Lamination (mm) 
                 — 
                 2.81 
                 3.94 
                 2.98 
                 3.32 
               
               
                 Proximal Jacket Wall Thickness Pre- 
                 — 
                 0.113 
                 0.225 
                 0.158 
                 0.203 
               
               
                 Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Volume of Proximal Jacket Per Unit  
                   
                 1.03 
                 2.94 
                 1.55 
                 2.24 
               
               
                 Catheter Length (mm 2 /F) 
                   
                   
                   
                   
                   
               
               
                 Volume of Distal Jacket Per Unit Catheter  
                   
                 0.78 
                 2.39 
                 1.10 
                 1.55 
               
               
                 Length (mm 2 /F) 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 9 
               
             
            
               
                   
               
               
                 Preferred dimensions for a Corrugated Catheter, expressed as a  
               
               
                 proportion of the catheter outer diameter (normalised against French size). 
               
            
           
           
               
               
               
            
               
                   
                   
                 Dimensions/French size 
               
            
           
           
               
               
               
               
            
               
                 Corrugated Catheter 
                   
                 Range 
                 Preferable 
               
            
           
           
               
               
               
               
               
               
            
               
                 Attribute 
                 Symbol 
                 Min 
                 Max 
                 Min 
                 Max 
               
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Catheter Outer Diameter  
                 OD 
                 0.288 
                 0.338 
                 0.325 
                 0.338 
               
               
                 (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Catheter Inner Diameter  
                 ID 
                 0.213 
                 0.300 
                 0.268 
                 0.293 
               
               
                 (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Distal Corrugation Depth  
                 d corr distal   
                 0.0031 
                 0.0275 
                 0.0100 
                 0.0250 
               
               
                 (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Distal Residual Depth  
                 d res   
                 0.0031 
                 0.0188 
                 0.0063 
                 0.0125 
               
               
                 (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Distal Corrugation Width  
                 W 
                 0.0031 
                 0.0313 
                 0.0188 
                 0.0300 
               
               
                 (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Rib fillet radius( mm/F) 
                 r rib   
                 0.0015 
                 0.0313 
                 0.0063 
                 0.0188 
               
               
                 Distal Liner Density 
                 — 
                 0.3 
                 1.2 
                 0.4 
                 0.9 
               
               
                 (g/cm 3 ) 
                   
                   
                   
                   
                   
               
               
                 Distal Liner Thickness  
                 t distal liner   
                 0.0019 
                 0.0128 
                 0.0031 
                 0.0095 
               
               
                 pre-assembly (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Proximal Liner ID (mm) 
                 — 
                 0.2231 
                 0.3150 
                 0.2750 
                 0.3000 
               
               
                 Proximal Liner wall 
                 t proximal liner   
                 0.0016 
                 0.0063 
                 0.0025 
                 0.0038 
               
               
                 thickness (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Atraumatic Tip Length  
                 — 
                 0.063 
                 0.250 
                 0.125 
                 0.156 
               
               
                 (Uncoiled section 80A  
                   
                   
                   
                   
                   
               
               
                 length distal to radio- 
                   
                   
                   
                   
                   
               
               
                 paque marker band) 
                   
                   
                   
                   
                   
               
               
                 (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Distal Helical Support  
                 ID Support   
                 0.238 
                 0.300 
                 0.263 
                 0.288 
               
               
                 Diameter (mm/F) 
                 Distal 
                   
                   
                   
                   
               
               
                 Distal Support Wire 
                 D coil  Distal 
                 0.010 
                 0.025 
                 0.011 
                 0.014 
               
               
                 Diameter (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Proximal Helical Support  
                 ID Support   
                 0.24 
                 0.30 
                 0.26 
                 0.29 
               
               
                 Diameter (mm/F) 
                 Proximal 
                   
                   
                   
                   
               
               
                 Proximal Helical Wire  
                 D coil   
                 0.014 
                 0.025 
                 0.017 
                 0.022 
               
               
                 Diameter (mm/F) 
                 Proximal 
                   
                   
                   
                   
               
               
                 Distance of ePTFE and  
                 — 
                 2 
                 20 
                 5 
                 15 
               
               
                 PTFE Joint from  
                   
                   
                   
                   
                   
               
               
                 transition from adjacent  
                   
                   
                   
                   
                   
               
               
                 jacket of a different 
                   
                   
                   
                   
                   
               
               
                 stiffness/diameter (mm) 
                   
                   
                   
                   
                   
               
               
                 Length of Lap Joint 
                 — 
                 0.6 
                 3.8 
                 1.1 
                 1.4 
               
               
                 (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Length of Interwoven  
                 — 
                 0.04 
                 2.5 
                 1.1 
                 1.4 
               
               
                 Section of Helical  
                   
                   
                   
                   
                   
               
               
                 Supports Overlap (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Number of interwoven  
                 — 
                 1 
                 28 
                 12 
                 14 
               
               
                 pitches in radial support 
                   
                   
                   
                   
                   
               
               
                 overlap 
                   
                   
                   
                   
                   
               
               
                 Corrugation Distal 
                 Corrugation 
                 0.013 
                 0.094 
                 0.050 
                 0.063 
               
               
                 Support Pitch (mm/F) 
                 Pitch Distal   
                   
                   
                   
                   
               
               
                 Proximal Support 
                 Corrugation 
                 0.013 
                 0.094 
                 0.038 
                 0.050 
               
               
                 Pitch (mm/F) 
                 Pitch Proximal   
                   
                   
                   
                   
               
               
                 Cinch Wire  
                 — 
                 0.006 
                 0.050 
                 0.024 
                 0.026 
               
               
                 Diameter (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Distal Jacket ID Pre 
                 — 
                 0.31 
                 0.48 
                 0.33 
                 0.37 
               
               
                 Lamination (mm/F) 
                   
                   
                   
                   
                   
               
               
                 Distal Jacket Wall 
                 0.31  
                 0.48 
                 0.33 
                 0.37 
                 0.31 
               
               
                 thickness Pre- 
                   
                   
                   
                   
                   
               
               
                 Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Proximal Jacket ID  
                 0.010 
                 0.019 
                 0.013 
                 0.016 
                 0.010 
               
               
                 Pre Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Proximal Jacket Wall  
                 0.31  
                 0.44 
                 0.33 
                 0.37 
                 0.31 
               
               
                 Thickness Pre- 
                   
                   
                   
                   
                   
               
               
                 Lamination (mm) 
                   
                   
                   
                   
                   
               
               
                 Volume of Proximal 
                 — 
                 0.013 
                 0.036 
                 0.019 
                 0.028 
               
               
                 Jacket Per Unit Catheter  
                   
                   
                   
                   
                   
               
               
                 Length (mm 2 /F) 
                   
                   
                   
                   
                   
               
               
                 Volume of Distal Jacket  
                 — 
                 0.010 
                 0.029 
                 0.014 
                 0.019 
               
               
                 Per Unit Catheter Length 
                   
                   
                   
                   
                   
               
               
                 (mm 2 /F) 
               
               
                   
               
            
           
         
       
     
     The invention is not limited to the embodiments described but may be varied in construction and detail.