Patent Description:
In coronary artery disease, the coronary arteries may be narrowed or occluded by atherosclerotic plaques or other lesions. These lesions may totally obstruct the lumen of the artery or may dramatically narrow the lumen of the artery. In order to diagnose and treat obstructive coronary artery disease it is commonly necessary to pass a guidewire or other instruments through and beyond the occlusion or stenosis of the coronary artery.

Percutaneous coronary intervention (PCI), also known as coronary angioplasty, is a therapeutic procedure used to treat the narrowed or stenotic section of the coronary artery of the heart due to coronary lesions or obstructions. A guide catheter may be used in PCI to provide support an easier passage for another catheter or device (micro catheter, stents, balloons, etc.) to access the target site. For example, a guide catheter can be inserted through the aorta and into the ostium of the coronary artery. Once seated in the opening or ostium of the artery to be treated, a guidewire or other instrument is passed through the lumen of the guide catheter and then inserted into the artery distal to the occlusion or stenosis. Another example for the use of a guide catheter is shown where the guide catheter can be inserted through the aorta and into the peripheral anatomy enabling access, for example, to the femoral artery down through the popliteal artery. This procedure allows for access to vasculature below the knee.

However, guide catheters may encounter certain difficulties. The anatomy in the area for placement, e.g., the coronary vasculature, may be tortuous and the lesions themselves may be comparatively non-compliant. Moreover, when crossing comparatively non-compliant lesions, a backward force sufficient to dislodge the guide catheter from the ostium of the artery being treated can be generated. For example, in order to improve backup support, <CIT>, assigned to Vascular Solutions, Inc. , discloses a coaxial guide catheter which is adapted to be passable within a guide catheter. The distal portion of the coaxial guide can be extended distally from the distal end of the guide catheter. The coaxial guide catheter includes a flexible tip portion defining a tubular structure having a lumen through which interventional cardiology devices such as stents and balloons can be inserted and a substantially rigid portion proximal of and more rigid than the flexible tip portion that defines a rail structure without a lumen.

Facilitating equipment delivery is the most common indication for using a guide catheter. Other indicates include, thrombectomy, facilitating interventions in chronic total occlusion (CTO)s and selective contrast injection into the vasculature.

As illustrated in <FIG>, which is a depiction of a commercial product "Guideliner®" from Vascular Solutions, Inc. , a guide catheter extension <NUM> includes a distal portion <NUM> having a full circumference, a half-pipe portion <NUM>, a collar transition <NUM> which provides a rapid-exchange type access point to insert interventional devices (e.g., balloons, stents, etc.), a push rod <NUM>, and a proximal tab <NUM> for manual manipulation of the guide catheter extension <NUM>.

Another device is Guidezilla® from Boston Scientific Corp. <FIG> depicts a commercial guide catheter extension product. Compared to <FIG>, this product lacks an explicit half-pipe section, and instead uses a skived or tapered collar transition which is directly connected to a push rod or rail.

To date the guide catheter extension devices disclosed or available requires construction of different tube portions of different characteristics and joining these tube portions together. For example, as disclosed in <CIT>, the catheter extension includes a soft tip, a reinforced portion that is made of braided or coil reinforced polymeric section (e.g., PTFE (polytetrafluoroethylene) liner and Pebax as the exterior), and a substantially rigid portion which may be made of stainless steel or nitinol tube. For the Guidezilla® catheter, the collar transition is made of a different material than the tubular portion which has a reinforced portion formed from multi-filament braided wire to reinforced the polymeric section. This structure makes fabrication complicated.

Prior art designs for catheter tube bodies that have varying degrees of flexibility along the long or longitudinal axis often employ spiral cuts or interrupted spiral cuts along part of the tube segment. Parameters of the spiral cuts, such as cut pitch angle, cut widths, cut lengths, etc., are varied in order to provide the varying degrees of flexibility to the catheter shaft.

US patent application <CIT> discloses a collarless guide extension catheter having a distal sheath including an outer layer, an inner layer and an intermediate reinforcing member disposed between both layers. The reinforcing member may be made from stainless steel and tubular in shape and may be replaced buy a conventional stent-like cut tube, having a variety of different cut patterns to provide for changes in flexibility or stiffness.

A boosting catheter is known form <CIT> to comprises a proximal shaft that is connected to a tubular distal end portion. The proximal shaft comprises a shaft lumen and extends into the tubular portion such that the shaft lumen extends into the distal tube. The tube may include an inner and outer liner and may include segments of varying flexibility. Chinese patent application <CIT> describes a similar medical device with a tubular member comprising a reinforcing coil that may be embedded in a resin layer or between liners. However, there remains a need for improved design for catheter extensions, and more generally, alternative designs for catheter tubes, that allow not only ease of fabrication, but also control of various characteristics of the tube, e.g., steerability, variable bending flexibility along the working length, pushability, collapse or kink resistance, etc., at any point along the tube.

The invention, as defined in independent claim <NUM> and subsequent claims <NUM> - <NUM>, comprises a guide catheter extension, comprising: a tube, having a proximal enc and a push rod that is connected to said tube at said proximal end; wherein said tube comprises at least one zone along a portion of the length of the tube, the zone comprising a plurality of units, wherein the units of the zone are distributed circumferentially around the tube in at least one first band, each unit of the zone comprises at least one cutout segment that is oriented around a centre of symmetry, wherein the centre of symmetry of each unit in the band is positioned equally from the centre of symmetry of an adjacent unit in the same band and the centre of symmetry of each unit is positioned at the same point relative to the circumference of the tube as the centre of symmetry of a second unit in a third band which is separated by a second band from the first band; wherein said tube portion has an outer diameter and said tube comprises a radially outwardly extending flare at said proximal end that has a greater diameter than the outer dimeter of said tube portion; wherein said tube is configured to be received inside a guide catheter having an inner diameter; and wherein said flare is configured to substantially seal against said inner diameter of said guide catheter.

In an embodiment, each unit comprises three cutout segments extending radially from a centre of symmetry of the unit, where each cutout segment of the unit is positioned <NUM>° degrees from the other cutout segments in the unit in the band. The tube can comprise seven zones, a first zone, a second zone, a third zone, a fourth zone, a fifth zone, a sixth zone and a seventh zone, each zone having is formed from a plurality of units, wherein rank order of cutout surface area and cut-pattern perimeter length is: unit of the first zone < unit of the second zone < unit of the third zone < unit of the fourth zone < unit of the fifth zone < unit of the sixth zone < unit of the seventh zone. The zones can be arranged in sequence as first zone, second zone, third zone, fourth zone, fifth zone, sixth zone and seventh zone.

In another embodiment, the cutout segments are in the shape of a hexagon in tube of the guide catheter extension.

In a further embodiment, the guide catheter extension can comprise: a tube comprising, at least one zone along a portion of the length of the tube, the zone comprising a plurality of units, where the units of the zone are distributed circumferentially around the tube in at least one band, each unit of the zone comprises at least one cutout segment that is oriented around a centre of symmetry, where the centre of symmetry of each unit in the band is positioned equally from the centre of symmetry of an adjacent unit in the same band; a flared bib, that is substantially perpendicular to the long axis of the tube, which has a greater diameter than the outer diameter of the tube; and, a push rod attached at the long end of the transition section.

In various embodiments, the diameter of the tube can taper from a proximal end to a distal end.

The tube of the guide catheter extension can further comprise a section where the tube has a spiral cut section along a portion of the length of the tube and the spiral cut section is contiguous with the zone of the tube. The spiral cut section can be an interrupted spiral cut.

The present invention generally relates to multiple cut-pattern designs for a tubular structure (or tube) of a medical device for interventional procedures that can be passed through a portion of a patient's vasculature or into other body lumens, such as guiding catheters, guide catheter extensions, micro-catheters, as well as other catheter tubes. A tube (or a portion thereof) may be substantially uniform in diameter across its entire length. Alternatively, the tube can have a varying diameter across its length, e.g., a tapered configuration. The tapering can be in any direction and may only be present along a portion of the tube. The tube can be made from a metallic material (e.g., stainless steel) or metal alloy, for example, a shape memory material such as nitinol which renders the tube kink resistant. Alternatively, the tube can be formed from polymers, glass filled polymers or a metal-polymer composite. The exterior surface of tube, which can have the desired cut or etched patterns, can be further encapsulated or covered with a polymeric jacket material, and the inner surface of the tube can be lined with a polymer inner lining which has a smooth, lubricous surface.

One embodiment of the tube cut patterns of the invention is shown in <FIG> and <FIG>. A tube <NUM> having a longitudinal axis <NUM> (L), a proximal end <NUM>, a distal end <NUM>, and a body or tube wall. The tube wall has cut patterns which include a plurality of zones, <NUM>-<NUM>, which arc arranged along the longitudinal axis L. The zones can be along any portion of the tube or a single zone may comprise the entire tube. The length of the tube is shown as LA. Each zone includes a plurality of units (or groups) of radially symmetric, cutout segments that are distributed around the circumference of the tube in a band or row. A band or row can have <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>,<NUM>,<NUM>,<NUM>,<NUM>,<NUM>, <NUM> to n units. In <FIG>and <FIG> there are <NUM> units in each band or row. The number of units per band or row may be the same or different in two different zones. As shown in <FIG>, a unit from each of the <NUM> zones is identified as <NUM>,<NUM>,<NUM>,<NUM>,<NUM>,<NUM>,<NUM>, respectively. Each unit of the cutout portions can include three cutout segments each segment extending radially from a centre point or centre of symmetry. The cutout segments have a three-fold rotational symmetry, where each cutout segment is rotated <NUM> degrees from an adjacent cutout segment about a centre of symmetry. Within each zone, all of the units of cutout segments may have an equal open surface area (i.e., the open surface area is the area enclosed by the contour of the segments in a contiguous manner) as well as an equal cut-pattern perimeter length, the length of a continuous line traced along the shape of the cutout segment. Across different zones, the units of cutout segments may have larger surface areas and increased cut-pattern perimeter length in zones when labelled in the figure with higher zone numbers, e.g., the open surface area ranking unit of zone <NUM> < unit of zone <NUM> < unit of zone <NUM> < unit of zone <NUM> < unit of zone <NUM> < unit of zone <NUM> < unit of zone <NUM> and the cut-pattern perimeter length ranking is unit of zone <NUM> < unit of zone <NUM> < unit of zone <NUM> < unit of zone <NUM> < unit of zone <NUM> < unit of zone <NUM> < unit ofwne7. The patterns of the cutout portions having the three-fold rotational symmetry about a central point of symmetry ( centre of symmetry) as shown can also generally referred to as the "triplex" pattern or "triplex" cut herein.

In <FIG>, the triplex zones <NUM>-<NUM> are shown as being arranged sequentially along the longitudinal axis <NUM> of the tube having a length LA. The configuration shown provides for a gradually decreasing uncut surface area coverage along the length of the tube from the proximal end <NUM> to the distal end <NUM>, enabling the tube <NUM> to have a gradually increasing bending flexibility from the proximal end <NUM> to the distal end <NUM>. The <NUM> zones in <FIG> are shown arranged in sequence, i.e., <NUM> to <NUM>, only for illustrative purpose. In other embodiments, the zones containing the units can be arranged in any order along the longitudinal axis to provide any desired change of bending flexibility at any point or section along the longitudinal axis. The tube can be provided with fewer, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM>, or more zones, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM> (higher numbers are also possible, e.g. <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> ton different zones). The zones, which have different cutout surface areas as well as different cut-pattern perimeter lengths, can also be arranged in any order, e.g., zone <NUM>, zone <NUM>, zone <NUM>, zone <NUM>, zone <NUM>, zone <NUM>, zone <NUM>, in order to control flexibility of the tube at any point along the length of the tube.

As shown in <FIG>, each of zones <NUM>-<NUM> can include two adjacent rows or bands (as used herein, the term, row or rows is used interchangeably with the term band or bands) of units of cutout segments (e.g., bands in zone <NUM> and bands in zone <NUM> are shown as <NUM>, <NUM> and <NUM>,<NUM>, respectively, <FIG>) each arranged around the circumference of the tube. The rows or bands may also be referred to as circumferential rows or bands. In a row or band, the units are distributed in a straight line around the circumference of the tube. For illustration only, the band comprising the units of zone <NUM> and zone <NUM> are shown with a dotted line through the centre of each band intersecting the centre of symmetry (Cs) for each unit; for zone <NUM>, the dotted lines are <NUM> and <NUM>, while for zone <NUM>, the dotted line is <NUM> (<FIG>). Other numbers of bands/rows of units in a zone are also possible, including, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> up to n bands or rows.

The spacing between units in a band is shown in <FIG> and is represented as de, where de is the distance between the centre of symmetry, Cs, of two adjacent units in the same band (sec, e.g., <NUM>). The spacing, de, is equal within a single band and may be constant across the length of the tube in different zones. The spacing between bands within a zone, e.g., zone <NUM>, zone <NUM> and zone <NUM>, is shown as dl (<NUM>-<NUM>), d2 (<NUM>-<NUM>) and d3 (<NUM>-<NUM>); dl = d2 = d3, where the spacing is measured between the lines, <NUM>,<NUM>,<NUM>,<NUM>,<NUM> and <NUM>, which run through the centre of symmetry, Cs, of the bands within each zone. The spacing between zones, e.g., zone <NUM> - zone <NUM>, d12 (<NUM>-<NUM>), zone <NUM>-zone <NUM>, d23 (<NUM>-<NUM>) and zone <NUM> - zone <NUM>, d34 (<NUM>-<NUM>); dI2 = d23 = d34, where the spacing is measured between the lines, <NUM>,<NUM>,<NUM>, <NUM>, <NUM>, <NUM> and <NUM>. In one embodiment, the spacing between bands within a zone may be equal to the spacing of two bands between two different zones, e.g., dl = d2 = d3 = d12 = d23 = d34. In other embodiments, the spacing between bands within a zone may be greater than or less than the spacing between the bands in two different zones, e.g., dl = d2 = d3 > d12 = d23 = d34 or dl = d2 = d3 < dI2 = d23 = d34.

The overall arrangement of one embodiment of the tube is shown in <FIG>. The boundaries of each zone are shown as follows: zone <NUM>,<NUM>,<NUM>, zone <NUM>,<NUM>, <NUM>, zone <NUM>, <NUM>, <NUM>, zone <NUM>,<NUM>,<NUM>, zone <NUM>,<NUM>,<NUM>, zone <NUM>,<NUM>,<NUM> and zone <NUM>,<NUM>,<NUM>. The boundaries of the zones overlap with each other. The units within each zone are shown as zone <NUM>, <NUM>, zone <NUM>,<NUM>, zone <NUM>,<NUM>, zone <NUM>,<NUM>, zone <NUM>,<NUM>, zone <NUM>,<NUM> and zone <NUM>,<NUM>.

As shown in <FIG>, all cutout segments of the units within a zone can have the same orientation or are in-phase with respect to the line through the centre of symmetry for each row, <NUM> and <NUM>; compare cutout segments <NUM>-<NUM>, <NUM>-<NUM> and <NUM>-<NUM>. The cutout segments in adjacent bands or rows within a zone can also have the same orientation or are in phase with respect to the line through the centre of symmetry for each row, <NUM> and <NUM>; compare, <NUM>-<NUM> and <NUM>-<NUM>. In other words, the corresponding cutout segments in one unit within a zone are parallel with the cutout segments in an adjacent unit. The centre of symmetry, Cs, of units within the same zone, but in adjacent bands is shifted by one unit as shown in <FIG>. Between two adjacent zones, e.g., zone <NUM> and zone <NUM>, the units are shifted around the circumference of the band such that a straight line, <NUM>, can be drawn between the centre of symmetry for units in the same zone or adjacent zones in every other band, e.g., <NUM>, <NUM>, <NUM>, <NUM>, etc. bands. The centre of symmetry, Cs, in different bands falls along the same line in every other band. <FIG> - reference lines <NUM> and <NUM>. In other words, the centre of symmetry of each unit is positioned at the same point on the circumference of the tube as the centre of symmetry of a second unit in a third, third, fifth, etc. band which is separated by one band from the first band.

Depending on the material as well as the structural requirements in terms of flexibility, the thickness of the tube at any point can vary, e.g., from about <NUM> to <NUM>, e.g., <NUM> to about <NUM>, about <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, etc. The inner diameter of the lumen (ID) of the tube portion can vary, e.g., from about <NUM> to about <NUM>, or from about <NUM> to about <NUM>, e.g., about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, etc. The outer diameter of the lumen (OD) of the tube can also vary, e.g., from about <NUM> to about <NUM>, e.g., about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>, about <NUM>. <NUM>, about <NUM>, about <NUM>, about <NUM>. <NUM>, about <NUM>, about <NUM>, about <NUM>, etc. The thickness of the tube wall, the inner diameter ID and the outer diameter OD can each be constant throughout the length of the tube, or vary along the length of the tube.

<FIG>, B-9A, B show a close-up image of units from zones <NUM>-<NUM>. The units in these figures are shown only as cutout segments, without overlapping units from other zones as is the case when the cutout segments are present in the tube (tube wall). <FIG> shows the unit from zone <NUM> with <NUM> cutout segments <NUM>,<NUM> and <NUM>. The cutout segment maybe formed by two linear portions 309a, 309b, capped by two curvilinear portions <NUM> and <NUM>. The curvilinear portions begin at positions <NUM> and <NUM>, respectively for cutout segment <NUM>. In one embodiment, the width of the cutout <NUM> divided by <NUM> equals the radius of the curvilinear portions <NUM>,<NUM>. The open surface area of the cutout segments <NUM>,<NUM> and <NUM> is <NUM>,<NUM> and <NUM>, respectively. In the embodiment shown, the cutout segments, <NUM>, <NUM> and <NUM> are positioned equally from the centre of symmetry, Cs, <NUM> by a distance equal to the width <NUM> divided by <NUM>. In other words, an imaginary circle <NUM> may be positioned between the cutout segments having a radius equal to the width of the cutout segment <NUM>/<NUM>. The cut-pattern perimeter length of the cutout pattern from zone <NUM> is shown in <FIG> and is the sum of perimeters of each of the three cutout segments, <NUM>+ <NUM>+ <NUM>.

<FIG> shows the unit from zone <NUM>. The cutout zone <NUM> is composed of three contiguous cutout segments <NUM>,<NUM>,<NUM> which have been merged into a single cutout pattern having an open surface area of407. Each cutout segment is composed of two, equal linear portions, 405a, 405b, and a curvilinear portion <NUM> starting at position <NUM>. The centre of symmetry, Cs, for the unit is shown as <NUM>. The linear portions of each cutout segment are connected by a curvilinear portion <NUM>; specifically, in the embodiment shown, the linear portion of cutout segment <NUM>, 405b, is connected by a curvilinear portion <NUM> to the linear portion 409a of the cutout segment <NUM>. The radius of curvature of the curvilinear portions <NUM> and <NUM> can vary. The width, i.e., the distance between the two linear portions 405a, 405b can be equal to, less than or greater than the width between the two linear portions shown in zone <NUM>, <NUM>. The cut-pattern perimeter length of the cutout pattern from zone <NUM> is shown in <FIG> and is <NUM>.

<FIG> shows the unit from zone <NUM>. The centre of symmetry of the unit is shown as <NUM> is composed of three contiguous, cutout segments <NUM>,<NUM>,<NUM> having an open surface area <NUM>. Each cutout segment is composed of two linear portions 504a, 504b, and a curvilinear portion <NUM>, <NUM> starting at position <NUM>. The open surface area of the curvilinear portion is shown in cross hatch as <NUM>. The shape of the curvilinear portion <NUM> can vary and only one embodiment is shown in the figure. The cutout segments are connected by a curvilinear portion <NUM> starting at position <NUM>. As illustrated in the figure, the two equal, linear portions 504a and <NUM> b are connected by a curvilinear portion <NUM>; the degree of curvature of the curvilinear portion <NUM> can vary. The width of the <NUM> between the two linear portions 504a, 504b can be equal to, less than or greater than the width of the between the two linear portions <NUM> in zone <NUM>, <FIG>. The length of the linear portions 504a, 504b is less than, equal to or the greater than the linear portions in zone <NUM>, 405a, 405b. In the embodiment shown the linear portions 504a = 504b < 405a = 405b. The cut-pattern perimeter length of the cutout pattern from zone <NUM> is shown in <FIG> and is <NUM>.

<FIG> shows the unit from zone <NUM>. The centre of symmetry, Cs, of the unit is shown as <NUM> is composed of three contiguous, cutout segments <NUM>,<NUM>,<NUM> having an open surface area <NUM>. Each cutout segment is composed of two linear portions 604a, 604b, and a curvilinear portion <NUM>, starting at position <NUM>. The open surface area of the curvilinear portion is shown in cross hatch as <NUM>. The shape of the curvilinear portion <NUM> can vary and only one embodiment is shown in the figure. The cutout segments are connected by a curvilinear portion <NUM> starting at position <NUM>. As illustrated in the figure, the two equal, linear portions 604a and 604b are connected by a curvilinear portion <NUM>; the degree of curvature of the curvilinear portion <NUM> can vary. The width of the <NUM> between the two linear portions 604a, 604b can be equal to, less than or greater than the width of the between the two linear portions <NUM> in zone <NUM>, <FIG>. The length of the linear portions 604a, 604b is less than, equal to or the greater than the linear portions in zone <NUM>, 505a, 505b. In the embodiment shown the linear portions 604a = 604b < 505a = 505b. The cut-pattern perimeter length of the cutout pattern from zone <NUM> is shown in <FIG> and is <NUM>.

<FIG> shows the unit from zone <NUM>. The centre of symmetry, Cs, of the unit is shown as <NUM> is composed of three contiguous, cutout segments <NUM>, <NUM>, <NUM> having an open surface area <NUM>. Each cutout segment is composed of two linear portions 704a, 704b, and a curvilinear portion <NUM>, starting at position <NUM>. The open surface area of the curvilinear portion is shown in cross hatch as <NUM>. The shape of the curvilinear portion <NUM> can vary and only one embodiment is shown in the figure. The cutout segments are connected by a curvilinear portion <NUM> starting at position <NUM>. As illustrated in the figure, the two equal, linear portions 704a and 704b are connected by a curvilinear portion <NUM>; the degree of curvature of the curvilinear portion <NUM> can vary. The width of the <NUM> between the two linear portions 704a, 704b can be equal to, less than or greater than the width of the between the two linear portions <NUM> in zone <NUM>, <FIG>. The length of the linear portions 704a, 704b is less than, equal to or the greater than the linear portions in zone <NUM>, 605a, 605b. In the embodiment shown the linear portions 704a = 704b < 605a = 605b. The cut-pattern perimeter length of the cutout pattern from zone <NUM> is shown in <FIG> and is <NUM>.

<FIG> shows the unit from zone <NUM>. The centre of symmetry, Cs, of the unit is shown as <NUM> is composed of three contiguous, cutout segments <NUM>, <NUM>, <NUM> having an open surface area <NUM>. Each cutout segment is composed of two linear portions 804a, 804b, and a curvilinear portion <NUM>, starting at position <NUM>. The open surface area of the curvilinear portion is shown in cross hatch as <NUM>. The shape of the curvilinear portion <NUM> can vary and only one embodiment is shown in the figure. The cutout segments are connected by a curvilinear portion <NUM> starting at position <NUM>. As illustrated in the figure, the two equal, linear portions 804a and 804b are connected by a curvilinear portion <NUM>; the degree of curvature of the curvilinear portion <NUM> can vary. The width of the <NUM> between the two linear portions 804a, 804b can be equal to, less than or greater than the width of the between the two linear portions <NUM> in zone <NUM>, <FIG>. The length of the linear portions 804a, 804b is less than, equal to or the greater than the linear portions in zone <NUM>, 705a, 705b. In the embodiment shown the linear portions 804a = 804b < 705a = 705b. The cut-pattern perimeter length of the cutout pattern from zone <NUM> is shown in <FIG> and is <NUM>.

<FIG> shows the unit from zone <NUM>. The centre of symmetry, Cs, of the unit is shown as <NUM> is composed of three contiguous, cutout segments <NUM>,<NUM>,<NUM> having an open surface area <NUM>. Each cutout segment is composed of two linear portions 904a, 904b, and a curvilinear portion <NUM>, starting at position <NUM>. The open surface area of the curvilinear portion is shown as a cross hatch <NUM>. The shape of the curvilinear portion <NUM> can vary and only one embodiment is shown in the figure. The cutout segments are connected by a curvilinear portion <NUM> starting at position <NUM>. As illustrated in the figure, the two equal, linear portions 904a and <NUM> b arc connected by a curvilinear portion <NUM>; the degree of curvature of the curvilinear portion <NUM> can vary. The width of the <NUM> between the two linear portions 904a, 904b can be equal to, less than or greater than the width of the between the two linear portions <NUM> in zone <NUM>, <FIG>. The length of the linear portions 904a, 904b is less than, equal to or the greater than the linear portions in zone <NUM>, 805a, 805b. In the embodiment shown the linear portions 904a = 904b < 805a = 805b. The cut-pattern perimeter length of the cutout pattern from zone <NUM> is shown in <FIG> and is <NUM>.

An overview of the transition of the units across zone <NUM> to zone <NUM> is shown in <FIG>. The following characteristics apply to the dimensions across the zones. The open surface area of the cutout areas across the different zones rank orders as: (<NUM>+ <NUM> + <NUM>) < <NUM> < <NUM> < <NUM> < <NUM> < <NUM> < <NUM>. The rank order of the open surface area of the curvilinear portion is: <NUM> < <NUM> < <NUM> < <NUM> < <NUM>. The rank of the linear portions is: 904a = 904b < 805a = 805b < 704a = 704b < 605a = 605b < 505a = 505b. The rank order of the cut-pattern perimeter lengths is (<NUM>+<NUM>+<NUM>) < <NUM> < <NUM> < <NUM> < <NUM> < <NUM> < <NUM>. The change in either open surface area or cut-pattern perimeter length across multiple zones can be linear, exponential, assume a step-wise or square wave function and be increasing, decreasing, constant, continuous or discontinuous.

Within any one zone, the cutout segments forming a unit may assume any symmetrical shape about a centre of symmetry, Cs. There may be <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or n cutout segments in a unit. The cutout segments may be continuous or separate. For example, the cutout segment may form a circle or a symmetrical, n-sided polygon, such as a hexagon or octagon. Different zones may have the same or different symmetrical shapes. The geometric rules, both within a zone as well as across a zone remain the same in these embodiments as they are for the triplex cutout segments described above. Specifically, the units are arranged in a band. A band or row can have <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> to n units. The spacing between units in a band represented as de, where de is the distance between the centre of symmetry, Cs, of two adjacent units in a band, de, is equal within a single band and may be constant across the length of the tube in different zones. The spacing between bands within a zone and across zones may be equal as well. All cutout segments of the units within a zone can have the same orientation or are in-phase with respect to the line through the centre of symmetry for each row or band. The cutout segments in adjacent bands or rows within a zone can also have the same orientation or arc in-phase with respect to the line through the centre of symmetry for each row. The centre of symmetry, Cs, of units within the same zone, but in adjacent bands is shifted. Between two adjacent zones, the units are shifted around the circumference of the band such that a straight line can be drawn between the centre of symmetry for units in adjacent zones. The centre of symmetry, Cs, in different bands falls along the same line in every other band. In other words, the centre of symmetry of each unit is positioned at the same point on the circumference of the tube as the centre of symmetry of a second unit in a third, third, fifth, etc. band which is separated by one band from the first band.

One tube may contain multiple zones. For example, the tube can be provided with <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM> (higher numbers are also possible, e.g. <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> ton different zones). If a tube contains multiple zones, then across different zones there may be a change in open surface area and cut-pattern perimeter length. For example, if the cutout segment is formed in the shape of a hexagon and there are seven zones, a first zone, a second zone, a third zone, a fourth zone, a fifth zone, a sixth zone and a seventh zone, then the rank order for the open surface area and cut pattern perimeter length is: unit of first zone < unit of second zone < unit of third zone < unit of fourth zone < unit of fifth zone < unit sixth zone. If there are equal number of units per zone, then the rank order applies to zones as well. The change in either open surface area or cut pattern perimeter length across multiple different zones can be linear, exponential or assume a step-wise or square wave function and be increasing, decreasing, constant, continuous or discontinuous.

In embodiments formed from other cutout segments, e.g., circles or n-sided polygons, the width across any uncut portion, may be varied, i.e., the width may be reduced. This reduction in width will result in an increase in the open surface area <NUM>. By increasing the open surface area, the uncut surface area within unit in any one zone, the flexibility of that portion composed of such units with increased open surface area of the cutout segments will increase.

The portion of the tube wall remaining after the cutout segments are removed may vary across the length of the tube and is inversely correlated with the open surface area of the cutouts. This inverse correlation is evident from <FIG> which show the cutout patterns of units, white or unmarked, contrasted with the remaining uncut surface of the tube, shown in dark colour, e.g., black, with stippling. The zones are labelled as followed: zone <NUM>, <FIG>, zone <NUM>, <FIG>, zone <NUM>, <FIG>, zone <NUM>, <FIG> and zone <NUM>, <FIG>. As is evident from the figures, the remaining dark colour, e.g., black with stippling or uncut material in the wall of the tube decreases as the open surface area of the cutout areas in the unit increases, i.e., the uncut area is inversely correlated with the cutout surface areas. The flexibility of the tube may be precisely controlled at any position along the tube by combining one or more zones at various positions along the length of the tube. Flexibility of the tube is positively correlated with the open surface area. In other words, as the open surface area of a cutout segment increases the flexibility of a zone composed of units having the larger cutout segments increases. Conversely, flexibility is inversely correlated with the uncut area; as the uncut surface area increases, flexibility decreases.

When zones are combined there may be a continuous transition in the remaining uncut area as shown in black across the various zones. The total uncut-area at any one point on the tube will depend on a number of factors, including the number of bands in each zone and the dimensions of the cutout segments (the open surface area of a particular unit). If the number of bands in each zone are constant, then the rank order is for the uncut surface area, unit of zone <NUM> > unit of zone <NUM> > unit of zone <NUM> > unit of zone <NUM> > unit of zone <NUM> > unit of zone <NUM> > unit of zone <NUM> (in other words, there is a fading of uncut area across zones) and the rank order of flexibility of the tube is zone <NUM> < zone <NUM> < zone <NUM> < zone <NUM> < zone <NUM> < zone <NUM> < zone <NUM> (flexibility is positively correlated with the open surface area and inversely correlated with the uncut area). The change in flexibility across multiple different zones can be linear, exponential or assume a step-wise or square wave function, increasing, decreasing, constant, discontinuous or continuous.

One embodiment where the number of bands of units in each zone are not the same is shown in <FIG>.

A unit in zone <NUM> is shown in <FIG>. The uncut area of the segment in the unit of zone <NUM> in <FIG> is shown in stripes. In zone <NUM>, the open surface area <NUM> of the cutout segment may be increased as follows. The centre of symmetry for the cutout segments comprising A, B, C is <NUM>. The figure shows portions of three other units from zone <NUM>, <NUM>, <NUM>, and <NUM>. The width across any uncut portion, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> (shown only as sample points) may be varied, i.e., the width may be reduced. In one embodiment, the width <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may be equal. The width <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may be further reduced in a uniform or non-uniform manner. This reduction in width will result in an increase in <NUM> with a corresponding increase in the open surface area <NUM>. By increasing the open surface area, the uncut surface area within a unit in zone <NUM>, the flexibility of that portion composed of such units with increased open surface area of the cutout segments will increase. <FIG> and <FIG> show photomicrographs with a reduction in width of the uncut surface area or strut wall from <NUM>% and <NUM>%, respectively (the dimensions are show in micrometers, µMat the bars shown in the figures). In other embodiments, the reduction in width can be applied to any zone to increase the open surface area within one zone or across multiple zones, thereby altering flexibility.

The cutout segment patterns described here can be applied to a variety of flexible shaft devices, to replace, supplement or be combined with braiding and coil composite configurations with a single thin walled frame. By using different zone patterns along the shaft length, flexibility can be increased or decreased along the shaft length, as well as other characteristics of the tube, such as torque, flexibility, pushability, resistance to axial compression and stretch, maintaining lumen diameter and kink resistance.

The cutout segment patterns described here, as well as other cut features of the tube can be made by techniques commonly known in the art, e.g., by a solid-state, femtosecond laser cutting. The tube portion to be cut can be loaded on a mandrel and the relative movement between the laser beam and the tube portion can be controlled by a computer with preprogrammed with instructions to produce any desired cut patterns. Other material removal techniques commonly known would also include photo-etching, other laser platforms and electrical discharge machining (EDM),.

As shown in <FIG>, a tube <NUM> can include a section <NUM> that contains one or more zones of the triplex cut patterns described above, as well as a further section <NUM> that contain other cut patterns, e.g., a spiral cut-pattern <NUM>. The spiral cut section may be longer, equal to or shorter than the triplex cut patterns. The spiral cut section <NUM> may include several sub-sections that may have different spiral parameters, such as cut widths, gaps, pitches, etc., such that the bending flexibility along the spiral cut section can vary longitudinally as desired. Additionally, the spiral cut section may also include interrupted spiral cuts <NUM> where the spiral cuts do not form continuous spirals along the tube wall. Either or both of the spiral cut section and the triplex section can be encapsulated within an outer jacket and/or an inner lining. The spiral cut may be made using a laser, e.g., femto-second solid-state cutting laser, by removing tube material from the tube wall. A tube portion fabricated with spiral cuts can also be viewed as a ribbon or flat coil (made of portions of the remaining tube wall) wound helically about the longitudinal axis.

The tube may have several different spiral-cut patterns, including continuous and discontinuous. The spiral-cut sections may provide for a graduated transition in bending flexibility. For example, the spiral-cut-pattern may have a pitch that changes the width of the spiral cut ribbon, to increase flexibility in one or more areas. The pitch of the spiral cuts can be measured by the distance between points at the same radial position in two adjacent threads. In one embodiment, the pitch may increase as the spiral cut progresses from a proximal position to the distal end of the catheter. In another embodiment, the pitch may decrease as the spiral cut progresses from a proximal position of the catheter to the distal end of the catheter. In this case, the distal end of the catheter may be more flexible. By adjusting the pitch of the spiral cuts, the pushability, kink resistance, torque, flexibility and compression resistance oft he catheter may be adjusted.

Spiral-cut sections having different cut patterns may be distributed along any portion of the length of the tube. The spiral-cut patterns may be continuous (contiguous) or discontinuous along the length. of the tube. For example, there may be <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>,. , n spiral-cut sections along the length of the tube, wherein within each section a constant cut-pattern may be present but across different sections the cut patterns vary, e.g., in terms of pitch. Each section may also contain a variable pitch pattern within the particular section. Each spiral-cut section may have a constant pitch, e.g., in the range of from about <NUM> to about <NUM>, e.g., <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, etc. The pitch may also vary within each section. The pitches for different spiral-cut sections may be same or different. Alternatively, the tube may have a continuously changing spiral-cut-pattern along the length of the tube. The orientation or handedness of spiral cut sections in the tube may also vary among spiral-cut sections. Similar to what has been described with respect to continuous spiral-cuts herein, an interrupted spiral-cut-pattern can also have a varying pitch that decreases from a relatively rigid region to a relatively flexible region.

A tube with triplex cut patterns as described here can be used as a portion of a medical device, e.g., a catheter (which can also be referred to as a guide catheter extension). One embodiment, of the tube which is incorporated into the catheter is shown in <FIG>. As schematically shown in <FIG>, a catheter <NUM> (more particularly, a guide catheter extension) can include a tube portion <NUM> (a distal tube portion) having multiple zones of triplex patterns of varying surface area coverage as described above, a skived (angled entrance port) collar transition section <NUM> adjacent the distal tube portion <NUM> and having a tapered edge, the taper having a short end <NUM> (closest to the distal tip <NUM> of the catheter) and a long end <NUM> (furthest away from the distal tip <NUM>), a push rod (or wire/rail) <NUM> being attached or joined at the long end <NUM>. In one embodiment, the transition section <NUM> can be absent, in which case the guide catheter extension includes the push rod or tube <NUM> directly attached to the tube portion <NUM>. Further, although it is shown that the transition section <NUM> includes a straight taper <NUM> from the side view, it is understood that various other shapes for the taper can also be used, e.g., a convex curve, a concave curve, a curvilinear curve, or other more complex shapes (sinusoidal) (see e.g., the transition sections shown in <FIG>, <FIG>, <NUM>, <FIG>), such that a generally slanted lumen opening or mouth is formed which contains a generally decreased, enclosed circumferential portion along the longitudinal axis L of the catheter away from the distal end <NUM> (at the short end <NUM>, the enclosed circumferential portion is nearly <NUM> degrees, i.e., a full tube, while at the long end <NUM> the enclosed circumferential portion can be much smaller, e.g., from <NUM> degrees to about <NUM> degrees). The skived transition section <NUM> and the triplex cut-pattern tube portion <NUM> can be made from a same or single tube by laser cutting creating a single frame or sections. Alternatively, the tube could be composed of several different frames or sections situated or laid· end-to-end about a common centre axis. The push rod (or wire/rail) <NUM>, which can be made from a metallic material, such as stainless steel, can be joined with the skived transition section <NUM> by welding, interlocking or other any other bonding or fusing method.

<FIG> shows a flat or unrolled view of a portion of a guide catheter extension <NUM>. <FIG> shows a photo of the portion of guide catheter extension shown in <FIG>. The portion of guide catheter extension <NUM> includes a tube <NUM> having a single triplex pattern (where all units have the same cutout segments, i.e., the same open surface area and cut-pattern perimeter length), a skived collar transition section <NUM> which has a generally tapered edge having a short end <NUM> and a long end <NUM>, and an attachment tab <NUM> which is welded or bonded together with a push rod (wire/rail) <NUM>. As discussed above, all of1710, <NUM>, and <NUM> can be cut from a single tube by laser. At the short end <NUM> of the transition section <NUM>, a cut <NUM> can be made from an edge of the transition section <NUM> through a closest triplex unit feature <NUM>. The width of the cut <NUM> can vary. This cut allows the tube <NUM> to expand or open up under pressure during manufacturing the catheter assembly when the tube is passed over a mandrel. The pattern of cuts shown in <NUM> can vary. In the embodiment shown in 14B, the pattern forms a square wave pattern with a descending size, i.e., <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. In the embodiment shown, when rolled into a tube, the two square wave patterns come together to form a cage like structure which is flexible, allowing for entire structure to be maneuvered through a tortuous path or anatomy.

In one embodiment, transverse cuts made be introduced in the portion of the pattern showing the square wave pattern in order to increase flexibility of the section, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. The width of the transverse cuts may also vary depending on the degree of flexibility required. Although schematically, the transverse cuts are shown as lines in the figure, other designs may be used, including a square wave, sinusoidal or meandering pattern.

As illustrated in <FIG>, a tube <NUM> (or more particularly, a guide catheter extension) includes a distal (full) tube portion <NUM>, a skived collar transition section <NUM> having a generally tapered edge with varying degrees of an enclosed circumferential wall portion ( forming a slanted lumen opening) which has a short end <NUM> and a long end <NUM>, and a push rod (wire/rail) <NUM> connected to the long end <NUM> of the skived collar transition section <NUM>. The tube portion <NUM> of the catheter can include a generally longitudinal cut-pattern <NUM> such that the side wall of the tube portion <NUM> ( and the lumen enclosed therein) can be slightly opened upon an expansion force to facilitate manufacturing of the inner luminal portion of the tube or insertion of an interventional device into the slanted lumen opening of the transition section. Although schematically, the longitudinal cut is shown as a saw tooth line in the figure, other designs may be used, including a square wave, sinusoidal zig-zag, square-wave or meandering pattern; the width of the longitudinal cut can vary and periodicity, i.e., a repetitive pattern is not required. For example, the cut-pattern can be a straight line oriented in parallel with the long axis L of the catheter.

<FIG> shows the catheter <NUM> where the tube portion <NUM> has cut-pattern <NUM>. The cut-pattern <NUM> can start from the short end <NUM> and can extend either partially or fully along the tube. As illustrated in Figures ISA and 15B, the tube portion <NUM> may join with another tube portion <NUM> which does not contain a generally longitudinal cut pattern. The tube portion <NUM>, however, can contain other cut patterns, such as spiral cuts, interrupted spiral cuts, or triplex cut patterns as described herein.

<FIG> show a 3D rendering of the skived collar transition section <NUM> and the.

push/rod <NUM>. The push rod <NUM> may be formed from a separate piece and fused to long end <NUM> at the junction formed between <NUM> of the long end <NUM> and <NUM> of the push rod <NUM> by any bonding method, including, crimping, swaging, staking. Adhesive bonding, welding, brazing or soldering may also be used. The design of the joint is shown as a rectangular opening in the long end <NUM>. Any shape can be used in a lock and key framework so that the push rod <NUM> could snap fit into the long end <NUM>. As shown in <FIG>, the profile of the push rod <NUM> is flat with respect to the lumen <NUM> formed by the long end <NUM>.

<FIG> shows certain components of a distal portion <NUM> of a catheter tube ( e.g., a guide catheter extension). <FIG> shows the distal portion <NUM> as assembled from the components shown in <FIG>. <FIG> shows a partial sectional view of the distal portion <NUM> as assembled; <FIG> show partial views of a portion of the distal portion <NUM> as assembled near the distal tip (<FIG>) and a portion of the distal portion <NUM> as assembled away from the distal tip. As shown in <FIG>, the distal portion <NUM> having a proximal end <NUM> and a distal end <NUM>, and includes a skeletal tubular frame <NUM> having a single triplex cut pattern, an outer jacket <NUM>, an inner liner <NUM>, and a distal tip <NUM> disposed at the distal end <NUM>. The term skeletal tubular frame refers to the tube described previously in <FIG>, inclusive.

The tip portion has a proximal end <NUM> and a distal end <NUM>, where the distal end <NUM> form an inwardly bending curve forming an opening that has a diameter Dt smaller than that of the lumen Dc of the catheter tube. The distal tip <NUM> near the distal end <NUM> can include a number of cuts <NUM> to make the distal tip more bendable, i.e., smaller "nose cone" like end in order to minimize trauma of the blood vessel wall when the distal tip is being advanced into a patient's vasculature. Alternatively, the distal tip may have a straight tube configuration. The tip portion <NUM> can be made from a polymeric material into which a radiopaque material can be embedded or attached. Radiopaque fillers include gold, platinum, barium sulfate, bismuth subcarbonate, bismuth oxychloride, bismuth trioxide and tungsten. (http://www. fostercomp. com/products/radiopaque-additives, retrieved November <NUM>, <NUM>).

The outer jacket <NUM> can be made from a polymeric material, such as polyether block amide ( e.g., PEBA®); the inner liner <NUM> can also be made from polymeric material having improved lubricity, such as PTFE. The jacket can be made from a polymer, e.g., by enclosing the catheter tube with a co-extruded polymeric tubular structure of single of multiple layers and heat shrinking the tubular structure, or coating the catheter tube by dip coating or spraying. See, e.g., <CIT>. Alternatively, the outer jacket can be applied by electro spinning using various polymers, e.g., PTFE to create a fibrous mesh outer layer.

The polymer jacket material can be formed from nylon, polyether block amide, PTFE, FEP, PFA, PET, PEEK, etc. Further, the distal catheter portion (or the entire length of catheter) may be coated with a hydrophilic polymer coating to enhance increase lubricity when advancing through the parent guiding catheter or vascular anatomy. Hydrophilic polymer coatings can include polyelectrolyte and/or a non-ionic hydrophilic polymer, where the polyelectrolyte polymer can include poly(acrylamide-co-acrylic acid) salts, a poly(methacrylamide-co-acrylic acid) salts, a poly( acrylamide-co-methacrylic acid) salts, etc., and the non-ionic hydrophilic polymer may be poly(lactams ), for example polyvinylpyrollidone (PVP), polyurethanes, homo- and co-polymers of acrylic and methacrylic acid, polyvinyl alcohol, polyvinylethers, maleic anhydride based copolymers, polyesters, hydroxypropylcellulose, heparin, dextran, polypeptides, etc. See e.g., <CIT> and <CIT>.

The components shown in <FIG> can be assembled by heat shrinking the outer jacket <NUM> onto the skeletal tube frame <NUM>, which can fully embed the uncut or remaining portions of the patterned tube wall, i.e., the skeletal frame. <FIG> and <FIG>. The inner liner <NUM> can then be adhered with the outer jacket <NUM> by heat or other bonding methods (note, the outer jacket is shown with stippling and the inner lining is shown with cross hatching). The inner liner may be incorporated in the covering process for the outer jacket, but the degree to which it is incorporated is material dependent. As shown in <FIG>, the inner liner <NUM> can extend distally beyond the distal end of the skeletal tube <NUM> and directly fused with the body of the distal tip <NUM>. In <FIG>, the outer jacket and inner liner arc used to encapsulate the skeletal frame <NUM>. The skeletal frame <NUM> is also bound to the outer most surface of the inner liner <NUM>, as shown in <FIG>. Additionally, dip coating and forming a conformal cover as the outer surface, allows for capturing or embedding the skeletal frame (tube) between the layers thereby creating a composite outer jacket material. The tube itself or the skeletal tube frame can have a triplex, spiral or a combination of patterns or contain linked tubular portions as described here. Once fully assembled with the outer jacket <NUM> and inner layer <NUM>, the interior portion of the tube <NUM>, i.e., the lumen of the tube, is then completely enclosed within the skeletal tube frame <NUM>, the inner liner <NUM> and the outer jacket <NUM>. The skeletal frame, i.e., the tube, can also be used directly without an outer jacket or inner lining. When using either a coated or uncoated skeletal tube frame, the driving design factor is maintaining the flexibility of the tube as discussed previously.

The guide catheter extension can include a tube portion <NUM> having a fully enclosed lumen, a skived collar transition section <NUM> adjacent the distal tube portion <NUM> and having a generally tapered edge, and a proximal push rod (wire/rail) <NUM> attached to the transition section <NUM>. As illustrated in <FIG>, a sealer <NUM> can be fitted on the distal tube section <NUM> and near the transition section <NUM> to reduce the gap between the guide catheter extension and the surrounding guide catheter.

The sealer <NUM> can take various forms or configurations, as illustrated in <FIG>. As shown in <FIG>, the sealers <NUM> and <NUM> can be formed with a tubular base <NUM> and <NUM>, respectively, for engaging with the distal tube portion <NUM>. The sealer <NUM> can include a lateral extension or fin <NUM> spirally wound about the tubular base <NUM>. Alternatively, the sealer <NUM> can include wiping blade surfaces composed of a single or multiple set of fins or ridges <NUM> that are wound circumferentially about the tubular base <NUM> (i.e., perpendicular to the long axis of sealer). Alternatively, the sealer <NUM> can take the form of a spiral extrusion or filament <NUM>.

The sealer, <NUM>, <NUM>, <NUM>, can be made with various elastic polymeric material, preferably rubbery material having good lubricity, such as PEBA, PTFE, silicon, polyurethane or other fluoro-polymers. It can be fitted on the distal tube portion of the inner catheter by physical attachment ( e.g., elastic or frictional engagement), chemical bonding, adhering, welding, gluing, heat fused or any other bonding method. The inner diameters <NUM>, <NUM>, and <NUM> of the respective scalers <NUM>, <NUM>, and <NUM> can be substantially the same as, or slightly smaller than, the outer diameter of the distal tube portion of the guide catheter extension. The fins and the base in sealers <NUM>, <NUM> and <NUM>, <NUM>, respectively, can be made from the same material, or different materials. The heights of the fins of sealers <NUM>, <NUM>, and the diameter of the spiral wire <NUM> can be selected according to the inner diameter of the guide catheter. The outer diameter of the sealer(s) (including the height of the fin(s) in <NUM>/<NUM>, and the diameter of the spiral wire <NUM>) can be substantially the same as the inner diameter of the lumen of the guide catheter. The thickness of the fins can be selected such that the fins have sufficient pliability to allow the guide catheter extension to move axially within the guide catheter without significantly hampering its manoeuverability or tactile feedback to the physician, while remaining sufficient obstructive to impede flow or back flow of bodily fluids caused by the suction or aspiration on the outer surface of the catheter body.

The guide catheter extension can have a flare or flange <NUM>. The flare or flange can be used to close or reduce the gap between the guide catheter extension and an enclosing guide catheter. As illustrated in <FIG> and <NUM>, a guide catheter extension <NUM> can include a tube <NUM> having a proximal end <NUM>, which is connected to a push rod <NUM>. At the proximal end <NUM> there is a radially outwardly extending flare <NUM>, that may be substantially perpendicular to the long axis of the tube, which has a greater diameter than the outer diameter of the tube portion <NUM>, allowing a seal by a bib <NUM> to form between the guide catheter extension and the guide catheter <NUM>. In this embodiment, the tube terminates and then transitions directly to the push rod <NUM> without a transition through a skive.

Alternatively, the guide catheter <NUM> can include a distal tube portion <NUM>, a skived collar transition section <NUM> adjacent the distal tube portion <NUM> and a generally tapered edge having a short end <NUM> and a long end <NUM>, and a push rod <NUM> connected to the long end <NUM> of the transition section. A flare or flange <NUM> extends radially outwardly from the lumen opening formed by the tapered edge, and has a greater diameter than the outer diameter of the tube portion <NUM>. Thus, like the sealers described in connection with Figures I 7A-17D, and the flare or flange described in connection with <FIG>, the flare or flange can substantially close or seal the gap <NUM> by a bib <NUM> formed between the guide catheter <NUM> and the tube <NUM>, which may be covered by an outer jacket. This type of construction enables the guide catheter <NUM> and the guide catheter extension <NUM>, <NUM> to be used to inject contrast media into a target site in the patient's vasculature without leakage from the distal end of the guide catheter, i.e., the end closest to the push rod <NUM>. The flare together with the bib can also be used to facilitate smooth insertion of an interventional device, such as a balloon catheter or a stent.

Like the sealer described previously, the flares described in connection with <FIG> can be made from an elastic polymeric material, preferably rubbery material with good lubricity, such as PE8A, PTFE, silicon or other fluoro-polymers. The thickness of the flare can be selected to ensure the flares have sufficient pliability to allow the guide catheter extension to move axially within the guide catheter without significantly hampering its manoeuverability. For example, the thickness of the flare can be about <NUM> to about <NUM>, or about <NUM> to about <NUM>. The flares can be made as a separate piece and adhered to the proximal end <NUM> (in <FIG>) or the lumen opening of the transition section <NUM> (in Figure <NUM>), or made as an extension of an inner lining or outer jacket of the catheter extension 2400a or 2400b.

In one embodiment, and as illustrated by <FIG>, the guide catheter extension <NUM> includes a first tube portion <NUM>, a second tube portion <NUM> that has a gradually decreased diameter distally, and a third tube portion <NUM> which is at the distal end of the guide catheter extension and that can include a radiopaque tip <NUM>. The narrowing in diameter of the first and second tube portion may be produced by shape training of the nitinol tube using standard heating technology. (see http://www-personal. edu/~btrease/share/ SMA-Shape-Training-Tutarial. pdf, retrieved November1, <NUM>). The skived collar transition section <NUM> is disposed adjacent the first tube portion <NUM>. The transition section <NUM> has a generally tapered edge having a short end <NUM> and a long end <NUM>, and a flange <NUM> extends radially outwardly from the slanted lumen opening formed by the tapered edge. A push rod <NUM> is attached to the transition section <NUM>.

To use as an injection or aspiration system, both the guide catheter and the distal tube portion of the guide catheter extension should have a tube wall impermeable to fluid. Such impermeable tube wall can be made of a solid tube (made from a metal, a polym er, optionally with embedded braid or other reinforcing material), or made from a tube having spiral-cut or other cut patterns (such as the triplex cut patterns described herein) and sealed with a fluidimpermeable jacket, e.g., PEBA, nylon, PTFE, silicon or other material. The invention also relates to an aspiration system including a guide (or outer) catheter having a guide catheter lumen, an inner catheter (e.g., a guide catheter extension) movable within the inner guide catheter lumen, and the outer edge of a sealing member on the inner catheter. The inner catheter can be a guide catheter extension which can generally take the form of those described herein.

Each of the first tube portion <NUM> and the second tube portion <NUM> can be made from a metal or metal alloy (such as stainless steel (spring steel) or nitinol), or a braid or coil supported polymer material. The second tube portion <NUM> can include a spiral cut-pattern <NUM>, and the pitch of the spiral cut can be gradually decreased distally. An outer jacket and an inner lining can be coated onto the spiral-cut section to seal off the openings of the spiral cuts. The third tube portion <NUM> can be made from a material or construction more flexible or pliable than the material or construction for the first and the second tube portions <NUM> and <NUM>. For example, the third tube portion <NUM> can be formed from a polymeric material without a wire or braid support. In general, the flexibility of the three tube portions <NUM>, <NUM>, and <NUM> decreases distally. The flare and the bib together with the distally decreased lumen diameter allows easy insertion of variable-sized (diameter) interventional devices, such as micro-catheters, balloon catheters, and stents, into the lumen of the guide catheter extension <NUM>.

The guide catheter extension can be assembled together with a handle for pushing or torqueing. <FIG> depicts one embodiment of the non-functional catheter hub, holding tap or manoeuvring hub which can provide aid in torqueing the device once inside the anatomy, <NUM>. The push rod <NUM> is fused to the long end <NUM>. The lumen <NUM> runs through the guide catheter extension <NUM>. In the embodiment shown, there are two sealers configurations <NUM> and <NUM>.

Claim 1:
A guide catheter extension, comprising a tube, having a proximal end and a push rod that is connected to said tube at said proximal end;
wherein said tube comprises at least one zone along a portion of the length of the tube, the zone comprising a plurality of units, wherein the units of the zone are distributed circumferentially around the tube in at least one first band, each unit of the zone comprises at least one cutout segment that is oriented around a centre of symmetry, wherein the centre of symmetry of each unit in the band is positioned equally from the centre of symmetry of an adjacent unit in the same band and the centre of symmetry of each unit is positioned at the same point relative to the circumference of the tube as the centre of symmetry of a second unit in a third band which is separated by a second band from the first band;
wherein said tube is configured to be received inside a guide catheter having an inner diameter; and
wherein said tube portion has an outer diameter and
characterized in that
said tube comprises a radially
outwardly extending flare at said proximal end that has a greater diameter than the outer dimeter of said tube portion;
wherein said flare is configured to substantially seal against said inner diameter of said guide catheter.