Abstract:
An apparatus for imparting a tensile force to deflect a distal portion of a catheter while maintaining its exterior dimensions may include a handle grip including a cross-section of generally predetermined exterior dimensions, and a longitudinal axis. A flexible elongate member may include proximal and distal end portions, with the proximal end portion being coupled to the handle grip. An adjustment knob may include a cross-section of generally predetermined exterior dimensions, and is rotatably coupled to the handle grip around the longitudinal axis. An elongate deflection member may be operably coupled to the adjustment knob and to the distal end portion of the elongate member. Rotation of the adjustment knob may impart a tensile force to the deflection member thereby causing the distal end portion of the elongate member to deflect from a prior configuration while maintaining the generally predetermined exterior dimensions of the handle grip and the adjustment knob.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 12/346,653, filed 30 Dec. 2008, now allowed (the &#39;653 application), which is a continuation of U.S. application Ser. No. 11/023,667, filed 28 Dec. 2004, now U.S. Pat. No. 7,691,095 (the &#39;667 application). The &#39;653 application and the &#39;667 application are both hereby incorporated by reference as though fully set forth herein. 
    
    
     BACKGROUND OF THE INVENTION 
     a. Field of the Invention 
     The present invention relates to catheters and sheaths and methods of using catheters and sheaths. More particularly, the present invention relates to a fixed dimensional control handle for steerable catheters and sheaths and methods of manufacturing and using such an handle, with the control handle generally maintaining its exterior dimensions during operation thereof. 
     b. Background Art 
     Catheters (i.e., catheters or sheaths) that have flexible tubular bodies with deflectable distal ends and control handles for controlling distal end deflection are used for many noninvasive medical procedures. For example, catheters having conductive electrodes along the distal ends of their bodies are commonly used for intra-cardiac electrophysiology studies. The distal end of a catheter body is typically placed into a patient&#39;s heart to monitor and/or record the intra-cardiac electrical signals during electrophysiology studies or during intra-cardiac mapping. The orientation or configuration of the distal end is controlled via an actuator located on the catheter&#39;s control handle, which remains outside the patient&#39;s body. The electrodes conduct cardiac electrical signals to appropriate monitoring and recording devices that are operatively connected at the control handle. 
     Typically, a catheter body is cylindrical and electrically non-conductive. The catheter body includes a flexible tube constructed from polyurethane, nylon or other electrically non-conductive flexible material. The catheter body further includes braided steel wires or other non-metallic fibers in its wall as reinforcing elements. Each electrode has a relatively fine electrically conductive wire attached thereto and extending through the catheter body. The conductive wire extends from the distal end to a proximal end where electrical connectors such as plugs or jacks are provided to be plugged into a corresponding socket provided in a recording or monitoring device. 
     The distal portion of the catheter body is selectively deformed into a variety of curved configurations using the actuator on the control handle. The actuator is commonly internally linked to the distal portion of the catheter body by at least one deflection wire. Some catheter bodies employ a single deflection wire, which is pulled (i.e., placed in tension) by the actuator in order to cause the distal portion of the catheter body to deform. Other catheter bodies have at least two deflection wires, where the displacement of one wire (i.e., placing one wire in tension) results in the other wire going slack (i.e., the wire does not carry a compressive load). In such catheters, where the deflection wires are not adapted to carry compressive loads (i.e., the deflection wires are only meant to be placed in tension), the deflection wires are commonly called pull or tension wires. 
     To deform the distal end of the catheter body into a variety of configurations, a more recent catheter design employs a pair of deflection wires that are adapted such that one of the deflection wires carries a compressive force when the other deflection wire carries a tensile force. In such catheters, where the deflection wires are adapted to carry both compressive and tension loads, the deflection wires are commonly called push/pull or tension/compression wires and the corresponding catheter actuators are called push-pull actuators. U.S. Pat. No. 5,861,024 to Rashidi, which issued Jan. 19, 1999, is representative of a push-pull actuator of this type, and the details thereof are incorporated herein by reference. 
     Prior art control handles for controlling distal end deflection of catheter bodies have several drawbacks that adversely impact the handles&#39; ability to be operated precisely by a single hand. First, the control handles are often excessively bulky. Second, the control handles are often inadequate with respect to their ability to provide finely controlled deflection adjustment for the distal end of the catheter body. Third, the control handles often provide inadequate deflection wire travel for a desired medical procedure. Fourth, the control handles often have a mechanical advantage that is less than desirable and, as a result, require significant effort to operate on the part of a user. Fifth, once a desired body distal end deflection has been reached, the control handles typically require the physician to take a conscious step to maintain the catheter at the desired deflection. Sixth, the wire displacement mechanisms within the control handles have a tendency to permanently deform the deflection wires. Seventh, the wire displacement mechanisms within the control handles typically make it difficult, if not impossible, to provide a lumen that runs uninterrupted from the proximal end of the control handle to the distal end of the catheter body. 
     There is a need in the art for a catheter control handle that offers improved single hand operation and deflection adjustment of the distal end of the catheter body. There is also a need in the art for such a handle with a lumen there through. There is also a need in the art for a method of manufacturing and using such a control handle. 
     BRIEF SUMMARY OF INVENTION 
     A fixed dimensional and bi-directional steerable catheter control handle may include an apparatus for imparting a tensile force to deflect a distal portion of a catheter while maintaining its exterior dimensions. The apparatus may include a handle grip including generally oval or circular cross-sections of generally predetermined exterior dimensions, and a longitudinal axis. A flexible elongate member may include proximal and distal end portions, with the proximal end portion being coupled to the handle grip. An adjustment knob may include a generally circular cross-section of generally predetermined exterior dimensions, and may be rotatably coupled to the handle grip around the longitudinal axis of the handle grip. One or more elongate deflection members may be operably coupled to the adjustment knob and to the distal end portion of the elongate member. Rotation of the adjustment knob may impart a tensile force to the elongate deflection member thereby causing the distal end portion of the elongate member to deflect from a prior configuration while maintaining the generally predetermined exterior dimensions of the handle grip and the adjustment knob. 
     For the apparatus described above, in an embodiment, the elongate deflection member may include a filament, a braided cord, or a resin-based member. In an embodiment, the adjustment knob may be operably coupled to an intermediate body portion or a distal portion of the handle grip. In an embodiment, the elongate deflection member may include a first pull wire. The apparatus, in an embodiment, may include one or more additional pull wires operably coupled to the adjustment knob. 
     For the apparatus described above, in an embodiment, the apparatus may include means for simultaneously imparting a tensile force to the first pull wire and releasing a tensile force on the additional pull wire. The adjustment knob may include an interior surface forming an aperture generally orthogonally oriented with respect to the longitudinal axis of the handle grip, with the interior surface including one or more sets of threaded grooves which cooperate with the means. The means may include a pair of generally axially displaceable members disposed within the handle grip, and rotation of the adjustment knob may impart opposing forces to the axially displaceable members. 
     For the apparatus described above, in an embodiment, the elongate member may include one or more longitudinal lumens. In an embodiment, the apparatus may include one or more electrodes coupled to the elongate member. The elongate member, in an embodiment, may include a biocompatible electrically insulative material. The electrically insulative material may be a flexible material. Alternatively, the electrically insulative material may include a polyurethane material or a nylon material. The apparatus, in an embodiment, may include one or more reinforcing elements disposed within a portion of the elongate member. The reinforcing element may include braided members, which may include a conductive material. 
     For the apparatus described above, in an embodiment, the elongate member may include a segment of a braided metallic wire and/or a non-metallic fiber. The apparatus, in an embodiment, may include a hemostasis valve coupled to the handle grip. In an embodiment, an exterior surface of the adjustment knob may includes a generally longitudinal groove and/or a generally longitudinal protuberance. 
     For the apparatus described above, in an embodiment, the prior configuration may include a substantially straight configuration. In an embodiment, the elongate deflection member may include an elongate wire. In an embodiment, the apparatus may include an anchor ring coupled to the distal portion of the elongate member, and the elongate deflection member may include one or more elongate pull wires coupled to the anchor ring. 
     In an embodiment, an apparatus for imparting a tensile force to deflect a distal portion of a catheter while maintaining its exterior dimensions may include a handle grip including a cross-section of generally predetermined exterior dimensions, and a longitudinal axis. A flexible elongate member may include proximal and distal end portions, with the proximal end portion being coupled to the handle grip. An adjustment knob may include a cross-section of generally predetermined exterior dimensions, and be rotatably coupled to the handle grip around the longitudinal axis of the handle grip. One or more elongate deflection members may be operably coupled to the adjustment knob and to the distal end portion of the elongate member. Rotation of the adjustment knob may impart a tensile force to the elongate deflection member thereby causing the distal end portion of the elongate member to deflect from a prior configuration while maintaining the generally predetermined exterior dimensions of the handle grip and the adjustment knob. 
     For the apparatus described above, the handle grip may include a generally oval or circular cross-section, and in an embodiment, the adjustment knob may include a generally circular cross-section. 
     In an embodiment, an apparatus for imparting a tensile force to deflect a distal portion of a catheter while maintaining its exterior dimensions may include a substantially hollow handle grip having a tactile outer surface having a longitudinal axis. An adjustment knob having a tactile outer surface may be coupled to the handle grip approximately equidistant from the longitudinal axis. A relatively thin elongated flexible body may have a distal end portion and a proximal portion, with the proximal portion coupled to the handle grip. One or more elongated members may be operatively coupled to the adjustment knob and to the distal end portion. Means may be disposed within the handle grip and operatively coupled to the adjustment knob for imparting a tensile force to the elongated member when the adjustment knob is rotated about the longitudinal axis so that the distal end portion of the flexible body deflects from a first configuration to a second configuration. The tactile outer surfaces of the handle grip and the adjustment knob may be substantially unchanged when the flexible body is disposed in the first and second configurations. 
     For the apparatus described above, the handle grip may include a generally oval or circular cross-section, and in an embodiment, the adjustment knob may include a generally circular cross-section. 
     The foregoing and other aspects, features, details, utilities, and advantages of the invention will be apparent from reading the following description and claims, and from reviewing the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an isometric view of one embodiment of the present invention, which is a control handle for a catheter or sheath. 
         FIG. 2  is an isometric view of the handle exploded to show its various components. 
         FIG. 3  is a longitudinal sectional elevation of the handle taken along section line AA of  FIG. 1 . 
         FIG. 4  is an isometric view of the right and left slides with their respective deflection wires attached. 
         FIG. 5  is a side elevation of an exemplary slide illustrating a means of securing a deflection wire to the proximal end of the slide. 
         FIG. 6  is a longitudinal sectional elevation of the adjusting knob taken along section line AA of  FIG. 1 . 
         FIG. 7  is a plan view of another embodiment of the handle. 
         FIG. 8  is a side elevation of the handle depicted in  FIG. 7 . 
         FIG. 9  is an isometric view of the distal end of the handle depicted in  FIG. 7 . 
         FIG. 10  is a longitudinal sectional plan view of the handle taken along section line BB of  FIG. 9 . 
         FIG. 11  is a longitudinal sectional plan view of the knob taken along section line BB in  FIG. 9 . 
         FIG. 12  is a right side isometric view of the slides displaced about the wire guide. 
         FIG. 13  is a left side isometric view of the slides displaced about the wire guide. 
         FIG. 14  is a longitudinal sectional elevation of the handle grip taken along section line CC in  FIG. 7 . 
         FIG. 15  is a latitudinal sectional elevation of the handle grip taken along section line DD in  FIG. 8 . 
         FIG. 16  is an isometric view of the distal end of a control handle for a catheter wherein the handle has a through lumen. 
         FIG. 17  is an isometric view of the slides, the wire guide, the wire tubing, and the lumen illustrating the path the lumen takes through the handle. 
         FIG. 18  is an elevation view of the extreme proximal end surfaces of the slides as viewed from arrow A in  FIG. 17  and illustrating the path the lumen and wire tubing take into the passage formed by the channels of the slides. 
         FIG. 19  is an isometric view of the lumen, deflection wires, and electrical wires of the tube exiting the catheter body-retaining nut on the distal end of the handle. 
         FIG. 20  is an isometric view of another embodiment of the handle exploded to show its various components. 
         FIG. 21  is a longitudinal sectional elevation taken along section line ZZ in  FIG. 20 . 
         FIG. 22  is isometric views of the slides oriented to show their respective portions of the passage and their planar slide faces. 
         FIG. 23  is an isometric view of another embodiment of the handle exploded to show its various components. 
         FIG. 24  is a longitudinal sectional elevation of the handle taken along section line YY of  FIG. 23 . 
         FIG. 25  is the same longitudinal sectional elevation of the adjusting knob as depicted in  FIG. 24 , except the adjusting knob is shown by itself. 
         FIG. 26  is a side elevation of the slides. 
         FIG. 27A  is a latitudinal sectional elevation of the handle, as taken along section line XX in  FIG. 24 , wherein the wire guide has a square cross section. 
         FIG. 27B  is the same latitudinal sectional elevation depicted in  FIG. 27A , except the wire guide has a circular cross section and a key/groove arrangement. 
         FIG. 28  is a side elevation of one embodiment of the wire guide equipped with a groove. 
         FIG. 29  is a longitudinal sectional elevation of another embodiment of the handle taken along section line YY of  FIG. 23 . 
         FIG. 30  is a longitudinal sectional plan view of the handle depicted in  FIG. 29  taken along section line VV in  FIG. 23  and wherein section line VV forms a plane that is perpendicular to the plane formed by section line YY in  FIG. 23 . 
         FIG. 31  is an isometric view of one embodiment of the wire guide. 
         FIG. 32  is a latitudinal sectional elevation of the handle as taken along section line WW in  FIG. 29 . 
         FIG. 33  is a longitudinal sectional elevation of the handle taken along section line AA of  FIG. 1 . 
         FIG. 34  is a side elevation of an exemplary slide employed in the embodiment depicted in  FIG. 33 . 
         FIG. 35  is a longitudinal sectional elevation of the adjusting knob taken along section line AA of  FIG. 1 . 
         FIG. 36  is a diagrammatic illustration of the control handle of the subject invention being employed in a surgical procedure on a patient. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring  FIG. 1  is an isometric view of one embodiment of the present invention, which is a control handle  2  for a flexible tubular, body  4  of a catheter  5 . Throughout this specification, the term catheter is meant to include, without limitation, catheters, sheaths and similar medical devices. As shown in  FIG. 1 , in one embodiment, the distal end of the handle  2  is connected to the catheter body  4  and the proximal end of the handle  2  is connected to tubing  6  that contains electrical wire and extends to an electrical connector  8 . The handle  2  includes an adjusting knob  10  and a handle grip  12 . As will become clear from this specification, the handle  2  of the present invention is advantageous in that it is compact and allows a user to manipulate the catheter body&#39;s extreme distal end  14  in a bi-directional manner by pivoting the adjusting knob  10  relative to the handle grip  12  in one direction or the other about the longitudinal axis of the handle  2 . Furthermore, in one embodiment, the handle  2  has a lumen that runs uninterrupted from the proximal end of the handle  2  to the extreme distal end  14  of the catheter body  4 . This lumen can be used to provide contrast injection for guide wire insertion. 
     For a more detailed discussion of the handle  2 , reference is now made to  FIGS. 2 and 3 .  FIG. 2  is an isometric view of the handle  2  exploded to show its various components.  FIG. 3  is a longitudinal sectional elevation of the handle  2  taken along section line AA of  FIG. 1 . 
     As shown in  FIGS. 2 and 3 , the adjusting knob  10  is pivotally attached to a mounting shaft (i.e., a slide base or base portion)  16  contained within the handle grip  12 . To pivotally attach the knob  10  to the mounting shaft  16 , a dowel pin  18  is inserted into a pinhole  20  in the distal end of the shaft  16  and mates with a groove  22  in a hub portion  23  of the knob  10 . A silicone o-ring  24  exists between the hub portion  23  of the knob  10  and the distal end of the shaft  16 . 
     As indicated in  FIGS. 2 and 3 , a wire guide  26  is positioned within the adjusting knob  10  and is held in place by a retaining ring  28 . A right slide or member  30  and a left slide or member  32  are slideably positioned within a slot (i.e., a slide compartment)  34  in the mounting shaft  16 . A catheter body-retaining nut  36  is used to secure the catheter body  4  to the distal end of the wire guide  26 . 
     As illustrated in  FIG. 3 , a pair of deflection wires  38  extend from the extreme distal end  14  of the body  4 , through the body  4 , the wire guide  26  and a passage  40  formed between the two slides  30 ,  32 , to a point near a proximal portion of the slides  30 ,  32 . Each wire  38  then affixes to an individual slide  30 ,  32  via a retention screw  42 . 
     For a more detailed discussion of the slides  30 ,  32  and their relationship to the deflection wires  38 , reference is now made to  FIG. 4 , which is an isometric view of the deflection wires  38   a ,  38   b  attached to the right and left slides  30 ,  32 . As shown in  FIG. 4 , the slides  30 ,  32 , which are mirror images of each other, each have a rectangular box-like proximal portion  44  and a half-cylinder distal portion  46 . Each proximal portion  44  has a generally planar outer sidewall and bottom wall. These planar surfaces slideably displace against the generally planar sides and bottom of the slot  34 , which act as thrust surfaces for the slides  30 ,  32 . 
     Each half-cylinder distal portion  46  is hollowed out along its longitudinal axis to form the passage  40  through which the deflection wires  38   a ,  38   b  and, as indicated in  FIG. 3 , the narrow proximal portion of the wire guide  26  extend when the slides  30 ,  32  are in the assembled handle  2 . Each slide  30 ,  32  has a planar slide face  48  that is meant to slideably abut against the planar slide face  48  of the opposing slide  30 ,  32 . Thus, as illustrated in  FIG. 2 , when the planar slide faces  48  of the slides  30 ,  32  abut against each other and the extreme proximal ends of each slide  30 ,  32  are flush with each other, the half-cylinder distal portions  46  of each slide  30 ,  32  combine to form a complete cylinder with a channel or passage  40  there through. 
     As shown in  FIG. 4 , in one embodiment, the proximal end of each deflection wire  38   a ,  38   b  forms a loop  50  through which a retention screw  42  passes to secure the wire  38   a ,  38   b  to the proximal portion of the respective slide  30 ,  32 . As indicated in  FIG. 5 , which is a side elevation of an exemplary slide  30 , in one embodiment, the proximal end of each deflection wire  38  forms a knot  52 . The wire  38  passes through a hollow tension adjustment screw  54  and the knot  52  abuts against the head  55  of the screw  54 , thereby preventing the wire  38  from being pulled back through the screw  54 . In one embodiment, the screw&#39;s longitudinal axis and the longitudinal axis of the slide  30 ,  32  are generally parallel. Each tension adjustment screw  54  is threadably received in the proximal end of its respective slide  30 ,  32 . Tension in a wire  38  may be increased by outwardly threading the wire&#39;s tension adjustment screw  54 . Conversely, tension in a wire  38  may be decreased by inwardly threading the wire&#39;s tension adjustment screw  54 . 
     As can be understood from  FIG. 4 , in one embodiment where the wires  38   a ,  38   b  are intended to only transmit tension forces, the wires  38   a ,  38   b  may deflect or flex within an open area  45  defined in the proximal portion  44  of each slide  30 ,  32  when the slides  30 ,  32  displace distally. Similarly, as can be understood from  FIG. 5 , in another embodiment where the wires  38  are intended to only transmit tension forces, the wires  38  may slide proximally relative to the screw  54  when the slides  30 ,  32  displace distally. 
     As shown in  FIG. 4 , in one embodiment, the outer circumference of the half-cylinder distal portion  46  of the right slide  30  is threaded with a right-hand thread  56 , and the outer circumference of the half-cylinder distal portion  46  of the left slide  32  is threaded with a left-hand thread  58 . In one embodiment, the outer circumference of the half-cylinder distal portion  46  of the right slide  30  is threaded with a left-hand thread, and the outer circumference of the half-cylinder distal portion  46  of the left slide  32  is threaded with a right-hand thread. 
     For a better understanding of the relationship of the slide threads  56 ,  58  to the rest of the handle  2 , reference is now made to  FIG. 6 , which is a longitudinal sectional elevation of the adjusting knob  10  taken along section line AA of  FIG. 1 . As indicated in  FIG. 6 , a cylindrical hole or shaft  60  passes through the knob  10  along the knob&#39;s longitudinal axis. In the hub portion  23  of the knob  10 , the inner circumferential surface of the shaft  60  has both right hand threads  62  and left hand threads  64 . These internal threads  62 ,  64  of the knob  10  mate with the corresponding external threads  56 ,  58  of the slides  30 ,  32 . More specifically, the right internal threads  62  of the knob  10  mate with the right external threads  56  of the right slide  30 , and the left internal threads  64  of the knob  10  mate with the left external threads  58  of the left slide  32 . 
     Thus, as can be understood from  FIGS. 2 ,  3 ,  4  and  6 , in one embodiment, as the knob  10  is rotated clockwise relative to the longitudinal axis of the handle  2 , the internal and external right threads  62 ,  56  engage and the internal and external left threads  64 ,  58  engage, thereby causing simultaneous opposed displacement of the right and left slides  30 ,  32  longitudinally within the slot  34  in the handle  10 . Specifically, because of the threading arrangement of the knob  10  and the slides,  30 ,  32 , the right slide  30  moves distally within the slot  34  and the left slide  32  moves proximally within the slot  34  when the knob  10  is rotated clockwise relative to the handle grip  12  of the handle  2 . Conversely, when the knob  10  is rotated in a counterclockwise manner relative to the handle grip  12  of the handle  2 , the right slide  30  moves proximally within the slot  34  and the left slide  32  moves distally within the slot  34 . 
     As can be understood from  FIGS. 4 and 6 , when the knob  10  is rotated such that the right slide  30  is urged distally and the left slide  32  is urged proximally, the deflection wire  38   a  connected to the right slide  30  is placed into compression and the deflection wire  38   b  connected to the left slide  32  is placed into tension. This causes the extreme distal end  14  of the catheter body  4  to deflect in a first direction. Conversely, when the knob  10  is rotated such that the right slide  30  is urged proximally and the left slide  32  is urged distally, the deflection wire  38   a  connected to the right slide  30  is placed into tension and the deflection wire  38   b  connected to the left slide  32  is placed into compression. This causes the extreme distal end  14  of the catheter body  4  to deflect in a second direction that is opposite the first direction. 
     The control handle  2  of the present invention as described has several advantages. First, the handle  2  is compact and may be operated with a single hand. Second, the threaded slides  30 ,  32  and knob  10  allow a physician to make fine, controlled adjustments to the bend in the distal end  14  of the catheter body  4 . Third, once the knob  10  is rotated so as to cause a bend in the distal end  14  of the catheter body  4 , the threads  56 ,  58 ,  62 ,  64  interact to maintain the bend without requiring any action on the physician&#39;s part. Fourth, because the slides  30 ,  32  simply displace distally and proximally along the longitudinal axis of the handle  2 , they are less likely to permanently deform the wires  38  as compared to the wire displacement mechanisms in some prior art handles. Fifth, the threads  56 ,  58 ,  62 ,  64  are mechanically advantageous in that they provide increased deflection wire travel and reduced actuation effort for the physician, as compared to some prior art handles. 
     While  FIGS. 2-6  depict an embodiment where the slides  30 ,  32  have external threads  56 ,  58  and the knob  10  has internal threads  62 ,  64 , in other embodiments the threading arrangement is reversed. For a discussion of one such embodiment, reference is made to  FIGS. 33-35 .  FIG. 33  is a longitudinal sectional elevation of the handle  2  taken along section line AA of  FIG. 1 .  FIG. 34  is a side elevation of an exemplary slide employed in the embodiment depicted in  FIG. 33 .  FIG. 35  is a longitudinal sectional elevation of the adjusting knob taken along section line AA of  FIG. 1 . 
     A comparison of the embodiment depicted in  FIGS. 33-35  to the embodiment depicted in  FIGS. 3 ,  5  and  6  reveals that the two embodiments are generally the same, except as will be described in the following discussion of  FIGS. 33-35 . Reference numbers utilized in  FIGS. 33-35  pertain to the same or similar features identified by the same reference numbers in  FIGS. 3 ,  5  and  6 . 
     As shown in  FIG. 33 , the adjusting knob  10  is pivotally attached to a mounting shaft (i.e., a slide base or base portion)  16  contained within the handle grip  12 . A wire guide  26  is positioned within the adjusting knob  10 . Like the embodiment depicted in  FIG. 2 , the embodiment illustrated in  FIG. 33  includes a right slide or member  30  and a left slide or member  32  that are slideably positioned within a slot (i.e. a slide compartment)  34  in the mounting shaft  16 . 
     As can be understood from  FIG. 34 , the slides  30 ,  32 , which are mirror images of each other, each have a rectangular box-like proximal portion  44  and a distal portion  46  that may be rectangular or half-cylindrical. Each proximal portion  44  has a generally planar outer sidewall and bottom wall. These planar surfaces slideably displace against the generally planar sides and bottom of the slot  34 , which act as thrust surfaces for the slides  30 ,  32 . 
     Each distal portion  46  is hollowed out to form half of a cylindrical passage  40  that is created when the slides  30 ,  32  are abutted against each other in a side-by-side relationship. Thus, each distal portion  46  of each slide  30 ,  32  includes an inner circumferential surface, which when combined with the inner circumferential surface of the other slide  30 ,  32 , defines the cylindrical passage  40 . 
     As indicated in  FIG. 34 , in one embodiment, the inner circumferential surface of the right slide  30  is threaded with a right-hand thread  56 . Similarly, as can be understood from  FIG. 34 , the inner circumferential surface of the left slide  32  is threaded with a left-hand thread  58 . Thus, the distal portion  46  of each slide  30 ,  32  is equipped with internal threads. In another embodiment, the inner circumferential surface of the right slide  30  is threaded with a left-hand thread  58 . Similarly, the inner circumferential surface of the left slide  32  is threaded with a right-hand thread  56 . 
     As indicated in  FIG. 35 , the knob  10  includes an outer hub  23   a  surrounding an inner hub  23   b . A space  65  exists between, and is defined by, the inner and outer hubs  23   a ,  23   b . The space  65  is adapted to receive the distal ends  46  of each slide  30 ,  32 . The outer circumferential surface of the inner hub  23   b  has both right hand threads  62  and left hand threads  64 . These external threads  62 ,  64  of the knob  10  mate with the corresponding internal threads  56 ,  58  of the slides  30 ,  32 . More specifically, the right external threads  62  of the knob  10  mate with the right internal threads  56  of the right slide  30 , and the left external threads  64  of the knob  10  mate with the left internal threads  58  of the left slide  32 . 
     As can be understood from  FIG. 33 , in one embodiment, as the knob  10  is rotated clockwise relative to the longitudinal axis of the handle  2 , the internal and external right threads  56 ,  62  engage and the internal and external left threads  58 ,  64  engage, thereby causing simultaneous opposed displacement of the right and left slides  30 ,  32  longitudinally within the slot  34  in the handle  10 . Specifically, because of the threading arrangement of the knob  10  and the slides,  30 ,  32 , the right slide  30  moves distally within the slot  34  and the left slide  32  moves proximally within the slot  34  when the knob  10  is rotated clockwise relative to the handle grip  12  of the handle  2 . Conversely, when the knob  10  is rotated in a counterclockwise manner relative to the handle grip  12  of the handle  2 , the right slide  30  moves proximally within the slot  34  and the left slide  32  moves distally within the slot  34 . 
     As can be understood from  FIG. 33 , when the knob  10  is rotated such that the right slide  30  is urged distally and the left slide  32  is urged proximally, the deflection wire  38  connected to the right slide  30  is placed into compression and the deflection wire  38  connected to the left slide  32  is placed into tension. This causes the extreme distal end  14  of the catheter body  4  to deflect in a first direction. Conversely, when the knob  10  is rotated such that the right slide  30  is urged proximally and the left slide  32  is urged distally, the deflection wire  38  connected to the right slide  30  is placed into tension and the deflection wire  38  connected to the left slide  32  is placed into compression. This causes the extreme distal end  14  of the catheter body  4  to deflect in a second direction that is opposite the first direction. 
     For a detailed discussion of another embodiment of the handle  2  of the present invention, reference is now made to  FIGS. 7 ,  8  and  9 .  FIG. 7  is a plan view of the handle  2 .  FIG. 8  is a side elevation of the handle  2 .  FIG. 9  is an isometric view of the distal end of the handle  1   
     As shown in  FIGS. 7-9 , the handle  2  includes an adjusting knob  10  on its distal end and a handle grip  12  on its proximal end. As can be understood from  FIGS. 7-9 , in one embodiment, the knob  10  has a generally circular cross-section and the handle grip  12  has a generally oval cross-section. In one embodiment, both the knob  10  and the handle grip  12  have generally circular cross-sections. The oval cross-section of the handle grip  12  is advantageous because it provides the physician with a tactile indication of the catheter&#39;s rotational position. 
     For a more detailed discussion of the components of the handle  2 , reference is now made to  FIG. 10 , which is a longitudinal sectional plan view of the handle  2  taken along section line BB of  FIG. 9 . As shown in  FIG. 10 , an o-ring  24  is located between the handle grip  12  and a groove in the knob  10 . The knob  10  is pivotally affixed to the handle grip  12  via a rotating retaining-ring  60  that resides within grooves in both the knob and the handle grip  12 . 
     As illustrated in  FIG. 10 , a catheter body-retaining nut  36  is threadably affixed to the distal end of a wire guide  26  that extends along the axial center of the knob  10 . As indicated in  FIG. 10  and more clearly shown in  FIG. 11 , which is a longitudinal sectional plan view of the knob  10  taken along section line BB in  FIG. 9 , a cylindrical hole or shaft  60  passes through the knob  10  along the knob&#39;s longitudinal axis. The inner circumferential surface of the shaft  60  has both right hand threads  62  and left hand threads  64  that extend towards the distal end of the knob  10  from a hub portion  23  of the knob  10 . As shown in  FIG. 11 , in one embodiment, the knob  10  is a singular integral piece. 
     As indicated in  FIG. 10 , a right slide  30  and a left slide  32  are longitudinally displaceable within the handle  2  and about the proximal end of the wire guide  26 . As shown in  FIGS. 12 and 13 , which are, respectively, aright side isometric view of the slides  30 ,  32  displaced about the wire guide  26  and a left side isometric view of the slides  30 ,  32  displaced about the wire guide  26 , each slide  30 ,  32  has a planar slide face  48  that abuts and slideably displaces against the slide face  48  of the opposed slide  30 ,  32 . Also, each slide  30 ,  32  has a channel  40  that combines with the channel  40  of the opposed slide  30 ,  32  to form a passage  40  through which the proximal end of the wire guide  26  passes as the slides  30 ,  32  displace about the wire guide  26 . As shown in  FIG. 10 , the passage  40  formed by the channels  40  also provides a pathway along which the deflection wires  38   a ,  38   b  (represented by dashed lines in  FIG. 10 ) travel from a proximal portion of the slides  30 ,  32 , through the wire guide  26 , and onward to the extreme distal end  14  of the catheter body  4 . 
     As indicated in  FIGS. 12 and 13 , each slide  30 ,  32  has a half-cylinder distal portion  46  and a shorter and wider half-cylinder proximal portion  47 . The right slide  30  has a right-handed thread  56  on its distal portion  46 . Similarly, the left slide  32  has a left-handed thread  58  on its distal portion  46 . Thus, as can be understood from  FIG. 10 , when the knob  10  is rotated in a clockwise direction relative to the handle grip  12 , the right handed threads  62  within the knob  10  engage the right handed threads  56  of the right slide  30 , and the left handed threads  64  within the knob  10  engage the left handed threads  58  of the left slide  32 . As a result, the right slide  30  is distally displaced within the handle  2  and the left slide  32  is proximally displaced within the handle  2 . Accordingly, the deflection wire  38   a  attached to the right slide  30  is pushed (i.e., subjected to a compressive force) and the deflection wire  38   b  attached to the left slide  32  is pulled (i.e., subjected to a tension force). Conversely, if the knob is rotated counterclockwise, the opposite displacement of the slides  30 ,  32  and deflection wires  38   a ,  38   b  will occur. 
     As indicated in  FIG. 10 , each deflection wire  38   a ,  38   b  is attached to the proximal portion  47  of its respective slide  30 , 32  via retention screws  42 . The retention screws, which are more clearly illustrated in  FIGS. 12 and 13 , are threadably mounted in the proximal portions  47 . 
     As shown in  FIGS. 12 and 13 , each half-cylindrical proximal portion  47  of a slide  30 ,  32  has an upper and lower planar notch  64  adjacent their respective planar slide faces  47 . The function of these notches  64  may be understood by referring to  FIGS. 14 and 15 . 
       FIG. 14  is a longitudinal section elevation of the handle grip  12  taken along section line CC in  FIG. 7 .  FIG. 15  is a latitudinal section elevation of the handle grip  12  taken along section line DD in  FIG. 8 . As shown in  FIGS. 14 and 15 , the handle grip  12  is one integral piece having an interior cylindrical void  66  in which the proximal portions  47  of the slides  30 ,  32  may displace as indicated in  FIG. 10 . 
     As shown in  FIGS. 14 and 15 , upper and lower ribs  68  extend from the walls that form the interior cylindrical void  66 . The ribs  68  run longitudinally along a substantial portion of the cylindrical void&#39;s length. As can be understood from  FIGS. 12-15 , the upper planar notches  64  on the proximal portions  47  of the slides  30 ,  32  interface with, and displace along, the upper rib  68  as the slides  30 ,  32  displace within the cylindrical void  66 . Similarly, the lower planar notches  64  on the proximal portions  47  of the slides  30 ,  32  interface with, and displace along, the lower rib  68  as the slides  30 ,  32  displace within the cylindrical void  66 . Thus, the ribs  68  act as thrust surfaces for the slides  30 ,  32 . 
     For a detailed discussion of another embodiment of the handle  2  depicted in  FIGS. 7-15 , reference is now made to  FIG. 16 .  FIG. 16  is an isometric view of the distal end of a control handle  2  for a catheter  5  wherein the handle  2  and catheter body  4  have a through lumen  70 . As shown in  FIG. 16 , in one embodiment, the lumen  70  and the electrical wire tube  6 , which extends to the electrical connector  8 , pass through strain reliefs  71  and into the proximal end of the handle grip  12 . In one embodiment, the lumen  70  terminates at its proximal end with a stopcock  72 . In one embodiment, the stopcock  72  has a hemostasis seal  74  that can be utilized for guide wire insertion. While a long flexible length of lumen  70 , as depicted in  FIG. 16 , provides motion isolation while inserting contrast from a syringe, in one embodiment, the lumen  70  does not extend from the handle grip  12 . Instead, the stopcock  72  or luer fitting is simply attached to the lumen  70  where it exits the proximal end of the handle  12 . 
     For a better understanding of the path of the lumen  70 , reference is now made to  FIGS. 17 ,  18  and  19 .  FIG. 17  is an isometric view of the slides  30 ,  32 , the wire guide  26 , the wire tubing  6 , and the lumen  70  illustrating the path the lumen  70  takes through the handle  2 .  FIG. 18  is an elevation view of the extreme proximal end surfaces of the slides  30 ,  32  as viewed from arrow A in  FIG. 17  and illustrating the path the lumen  70  and wire tubing  6  take into the passage  40  formed by the channels  40  of the slides  30 ,  32 .  FIG. 19  is an isometric view of the lumen  70 , deflection wires  38   a ,  38   h , and electrical wires  76  of the wire tube  6  exiting the catheter body-retaining nut  36  on the distal end of the handle  2 . 
     As shown in  FIGS. 17 and 18 , the lumen  70  and the wire tubing  6  pass through their respective reliefs  71  and into the passage  40  formed by the channels  40  in each slide  30 ,  32 . In one embodiment, soon after the wire tubing  6  and the lumen  70  enter the passage  40 , the wires  76  of the wire tubing  6  exit the wire tubing  6  and are dispersed about the outer circumference of the lumen  70  as depicted in  FIG. 19 . 
     As illustrated in  FIG. 17 , in another embodiment, after the wire tube  6  and lumen  70  enter the passage  40 , the wire tube  6  and the lumen  70  continue on their pathway to the distal end  14  of the catheter body  4  by passing, in a side-by-side arrangement, through the remainder of the passage  40  formed into the slides  30 ,  32  and into an internal passage that extends along the longitudinal axis of the wire guide  26 . Near the end of the wire guide  26 , the wire  76  exists the wire tube  6 . The wire  76 , lumen  70  and deflection wires  38   a ,  38   b  then pass into the catheter by exiting the catheter body-retaining nut  36  of the handle as indicated in  FIG. 19 . 
     For a detailed discussion of another embodiment of the handle  2 , reference is now made to  FIG. 20 , which is an isometric view of the handle  2  exploded to show its various components. As can be understood from  FIG. 20 , the features of the handle  2  depicted in  FIG. 20  are similar to the features of the handle depicted in  FIG. 2 , except the handle  2  depicted in  FIG. 20  is configured to have a relatively large, generally uniform in diameter, pathway extend the full length of the handle  2  (i.e., from the distal opening  102  in the wire guide  26 , through the passage  40  defined in the slides  30 ,  32  and through an exit hole  104  in the proximal end of the shaft  16 ). 
     The configuration of the handle  2  that allows a relatively large generally uniform in diameter pathway to pass through the length of the handle  2 , as depicted in  FIG. 20 , is more clearly shown in  FIG. 21 , which is a longitudinal sectional elevation taken along section line ZZ in  FIG. 20 . As illustrated in  FIG. 21 , in one embodiment, the pathway  100 , which includes the passage through the wire guide  26  and the passage  40  through the slides  30 ,  32 , is large enough that the catheter body  4  itself may pass through the pathway  100  and be connected to the proximal end of the shaft  16  at the exit hole  104 . Thus, in one embodiment, to prevent the catheter body  4  from rotating with the adjusting knob  10 , the catheter body  4  is affixed to the shaft  16  at the exit hole  104 . In one embodiment, the catheter body  4  runs the full length of the handle  4  as depicted in  FIG. 21 , except the body  4  is affixed to the wire guide  26  at or near the distal opening  102 . In other embodiments, the catheter body  4  is affixed to both the wire guide  26  at or near the distal opening  102  and the shaft  16  at the exit hole  104 . 
     As can be understood from  FIG. 21  and as more clearly depicted in  FIG. 22 , which is isometric views of the slides  30 ,  32  oriented to show their portions of the passage  40  and their planar slide faces  48 , the passage  40  is large enough in diameter to displace over the outer diameter of the wire guide  26 . As shown in  FIGS. 21 and 22 , a catheter body passage  110  passes through the proximal portion  44  of each slide  30 ,  32 , thereby allowing the slides  30 ,  32  to displace back and forth over the outer surface of the catheter body  4 . 
     As indicated in  FIG. 21 , in one embodiment, the catheter body  4  has an opening  111  in its wall that allows the wires  38  to exit the body  4  and connect to the slides  30 ,  32 . In one embodiment, the wires  38  connect to the slides  30 ,  32  via tension adjustment screws  54  as previously discussed. 
     Due to the configuration of the slides  30 ,  32 , the wire guide  26  and the shaft  16 , the catheter body  4  may run uninterrupted the full length of the handle  2 . As a result, electrical wiring  76  (see  FIG. 19 ) and a lumen  70  may be routed the full length of the handle  2  by way of the body  4 . 
     For a detailed discussion of another embodiment of the handle  2  of the present invention, reference is now made to  FIGS. 23 and 24 .  FIG. 23  is an isometric view of the handle  2  exploded to show its various components.  FIG. 24  is a longitudinal sectional elevation of the handle  2  taken along section line YY of  FIG. 23 . Generally speaking, the features of the handle  2  depicted in  FIGS. 23 and 24  are similar to the features of the handle depicted in  FIG. 20 , except the two embodiments employ different slider arrangements. For example, the embodiments depicted in  FIGS. 1-22  employ parallel slides or members  30 ,  32  (i.e., the slides  30 ,  32  exist within the handle  2  in a parallel or side-by-side arrangement). As will be understood from  FIGS. 23 and 24  and the following figures, in the embodiment of the handle  2  depicted in  FIGS. 23 and 24 , the slides or members  150 ,  152  exist within the adjustment knob  10  in a series arrangement (i.e., the slides  150 ,  152  are not parallel or side-by-side to each other, but are oriented end-to-end along a longitudinal axis of the handle  2 ). 
     As shown in  FIGS. 23 and 24 , the adjusting knob  10  is pivotally coupled to the distal end of the mounting shaft (i.e., base portion)  16 . The wire guide  26  extends through the center of the adjusting knob  10  and the mounting shaft  16 . The catheter body  4  is coupled to the distal end of the wire guide  26  and, in one embodiment, extends through the wire guide  26  and out of the proximal end of the mounting shaft  16 . 
     As shown in  FIGS. 23 and 24 , a distal slide  150  is located in a distal portion of the adjusting knob  10 , and a proximal slide  152  is located in a proximal portion (i.e., hub portion  23 ) of the adjusting knob  10 . As illustrated in  FIG. 24 , the outer surface of each slide  150 ,  152  has threads  154  that mate with threads  156  on an interior surface of the adjusting knob  10 . 
     As illustrated in  FIG. 24 , each deflection wire  38   a ,  38   b  travels along the interior of the wire guide  26  until it exits the wire guide  26  at a hole  157  in the sidewall of the wire guide  26 . Each deflection wire  38   a ,  38   b  then extends to the slide  150 ,  152  to which the deflection wire  38   a ,  38   b  is attached. In one embodiment, in order to attach to a slide  150 ,  152 , a deflection wire  38   a ,  38   b  passes through a passage  159  in the slide  150 ,  152  and attaches to a hollow tension adjustment screw  54  via a knot  52  as previously described in this Detailed Description. 
     For a better understanding of the orientation of the threads  154 ,  156 , reference is now made to  FIGS. 25 and 26 .  FIG. 25  is the same longitudinal sectional elevation of the adjusting knob  10  as it is depicted in  FIG. 24 , except the adjusting knob  10  is shown by itself.  FIG. 26  is a side elevation of the slides  150 ,  152 . 
     As shown in  FIGS. 25 and 26 , in one embodiment, the distal slide  150  has right hand threads  154  that engage right hand threads  156  in the distal portion of the adjusting knob  10 , and the proximal slide  152  has left hand threads  154  that engage left hand threads  156  in the proximal portion of the adjusting knob  10 . Thus, as can be understood from  FIGS. 23-26 , when the adjusting knob  10  is rotated relative to the mounting shaft  16  in a first direction about the longitudinal axis of the handle  2 , the slides  150 ,  152  will converge along the wire guide  26 , thereby causing the first wire  38  to be placed into tension and the second wire  38  to be compressed. As a result, the distal end  14  of the catheter body  4  will deflect in a first direction. Similarly, when the adjusting knob  10  is rotated in a second direction that is opposite from the first direction, the slides  150 ,  152  will diverge along the wire guide  26 , thereby causing the first wire  38  to be compressed and the second wire  38  to be placed into tension. As a result, the distal end  14  of the catheter body  4  will deflect in a second direction generally opposite from the first direction. 
     In one embodiment, to prevent the slides  150 ,  152  from simply rotating around the wire guide  26  when the adjusting knob  10  is rotated, the slides  150 ,  152  and wire guide  26  are configured such that the slides  150 ,  152  will displace along the wire guide  26 , but not rotationally around it. For example, as indicated in  FIG. 27A , which is a latitudinal sectional elevation of the handle  2  as taken along section line XX in  FIG. 24 , the wire guide  26  has a square cross section that mates with a square hole  162  running the length of the slide  150 ,  152 . The interaction between the square hole  162  and the square cross section of the wire guide  26  prevents a slide  150 ,  152  from rotating about the wire guide  26 , but still allows the slide  150 ,  152  to displace along the length of the wire guide  26 . 
     In another embodiment, as shown in  FIG. 27B , which is the same latitudinal sectional elevation depicted in  FIG. 27A , each slide  150 ,  152  has a hole  162  with a circular cross section. Each hole  162  runs the length of its respective slide  150 ,  152  and includes a key  160  that extends into the hole  162  from the interior circumferential surface of the hole  160 . The key  160  engages a groove or slot  158  that runs along the length of the wire guide  26  as depicted in  FIG. 28 , which is a side elevation of one embodiment of the wire guide  26 . The interaction between the key  160  and the slot  158  prevents a slide  150 ,  152  from rotating about the wire guide  26 , but still allows the slide  150 ,  152  to displace along the length of the wire guide  26 . 
     As shown in  FIGS. 27A and 27B , a hollow shaft  165  extends through the wire guide  26 . This allows a catheter body  4  with a lumen to extend completely through the handle  2  as shown in  FIG. 24 . 
     For a detailed discussion of another embodiment of the handle  2  that is similar to the embodiment depicted in  FIG. 23 , reference is now made to  FIGS. 29 and 30 .  FIG. 29  is a longitudinal sectional elevation of the handle  2  as if taken through section line YY of  FIG. 23 .  FIG. 30  is a longitudinal sectional plan view of the handle  2  as if taken through section line VV in  FIG. 23  and wherein section line VV forms a plane that is perpendicular to the plane formed by section line YY in  FIG. 23 . 
     As illustrated in  FIGS. 29 and 30 , the handle  2  includes an adjusting knob  10  pivotally coupled to the distal end of the mounting shaft (i.e., base portion)  16 . In one embodiment, the adjusting knob  10  includes a proximal end  170 , a distal end  172  and a threaded shaft  173 , which is connected to the proximal end  170  and extends distally along the longitudinal axis of the adjusting knob  10 . The threaded shaft  173  includes a distal end  174 , a proximal end  176 , a series of right hand threads  178  along a distal portion of the shaft  173 , and a series of left hand threads  180  along a proximal portion of the shaft  173 . 
     As shown in  FIGS. 29 and 30 , a distal slide  150  is located in a distal portion of the adjusting knob  10 , and a proximal slide  152  is located in a proximal portion (i.e., hub portion  23 ) of the adjusting knob  10 . Each slide has a hole  155  through which the threaded shaft  173  passes. The inner circumferential surface of the hole  155  for the distal slide  150  has right hand threads that mate with the right hand threads  178  on the distal portion of the shaft  173 . Similarly, the inner circumferential surface of the hole  155  for the proximal slide  152  has left hand threads that mate with the left hand threads  180  on the proximal portion of the shaft  173 . In other embodiments, the locations for the left and right threads are reversed. 
     As can be understood from  FIGS. 29 ,  30  and  31 , which is an isometric view of one embodiment of the wire guide  26 , a hollow center shaft  182  extends from the distal end of the wire guide  26 , through the threaded shaft  173  of the adjustment knob  10 , and to the proximal end of the base shaft  16 . Thus, in one embodiment, a catheter body  4  may be routed through the lumen  165  of the wire guide&#39;s hollow center shaft  182  to exit the proximal end of the handle  2 , as illustrated in  FIGS. 29 and 30 . 
     As illustrated in  FIG. 29 , each deflection wire  38   a ,  386  travels along the interior of the wire guide  26  until it exits the wire guide  26  at a hole  157  in the sidewall of the wire guide  26 . Each deflection wire  38   a ,  38   b  then extends to the slide  150 ,  152  to which the deflection wire  38   a ,  38   h  is attached. In one embodiment, in order to attach to a slide  150 ,  152 , a deflection wire  38   a ,  38   b  passes through a passage  159  in the slide  150 ,  152  and attaches to a hollow tension adjustment screw  54  via a knot  52  as previously described in this Detailed Description. 
     In one embodiment, as shown in  FIG. 29 , the deflection wire  38   b  leading to the proximal slide  152  passes through a second passage  161  in the distal slide  150 . The second passage  161  has sufficient clearance that the passage  161  may easily displace along the wire  38   b  when the distal slide  150  displaces distally and proximally. The second passage  161  serves as a guide that stiffens the wire  38   b  and helps to reduce the likelihood that the wire  38   b  will bend when compressed. 
     As can be understood from  FIGS. 29 and 30 , when the adjusting knob  10  is rotated relative to the mounting shaft  16  in a first direction about the longitudinal axis of the handle  2 , the slides  150 ,  152  will converge along the threaded shaft  173 , thereby causing the first wire  38   a  to be placed into tension and the second wire  38   b  to be compressed. As a result, the distal end  14  of the catheter body  4  will deflect in a first direction. Similarly, when the adjusting knob  10  is rotated in a second direction that is opposite from the first direction, the slides  150 ,  152  will diverge along the threaded shaft  173 , thereby causing the first wire  38   a  to be compressed and the second wire  38   b  to be placed into tension. As a result, the distal end  14  of the catheter body  4  will deflect in a second direction generally opposite from the first direction. 
     In one embodiment, to prevent the slides  150 ,  152  from simply rotating with the threaded shaft  173  within the adjusting knob  10  when the adjusting knob  10  is rotated, the slides  150 ,  152  and wire guide  26  are configured such that the slides  150 ,  152  will displace along the threaded shaft  173 , but not rotationally within the adjusting knob  10 . For example, as indicated in  FIGS. 31 and 32 , which is a latitudinal sectional elevation of the handle  2  as taken along section line WW in  FIG. 29 , the wire guide  26  has right and left semicircular portions  190  that oppose each other and extend along the length of the hollow center shaft  182  of the wire guide  26 . As shown in  FIG. 32 , the generally planar opposed faces  192  of the semicircular portions  190  abut against the generally planar side faces  194  of the slides  150 ,  152 . This interaction prevents a slide  150 ,  152  from rotating within the adjustment knob  10  when the knob  10  is rotated, but still allows the slide  150 ,  152  to displace along the length of the threaded shaft  173 . 
     As can be understood from  FIG. 36 , which is a diagrammatic illustration of the control handle  2  of the subject invention being employed in a surgical procedure on a patient  200 , the distal end  14  of the catheter body  4  is inserted into the patient  200  (e.g., intravenously via a body lumen  202  of the patient  200 , percutaneously, or via other avenues for entering the patient&#39;s body). The distal end  14  of the catheter body  4  is advanced until positioned in a selected location within the patient  200  (e.g., within a chamber  204  of the patient&#39;s heart  206  or other organ, with a body cavity of the patient, etc.). The distal end of the catheter body  4  is then deflected by rotating the adjustment knob  10  about a longitudinal axis of a base portion  16 . As can be understood from  FIGS. 1-35 , this causes the slides  30 ,  32  within the handle  2  to displace along the longitudinal axis in opposite directions. Since each slide  30 ,  32  is coupled to its respective deflection wire  38  and each deflection wire  38  runs through the catheter body  4  and is coupled to the distal end  14 , the distal end  14  of the catheter body  4  is deflected. 
     Although a number of embodiments of this invention have been described above with a certain degree of particularity, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this invention. For example, all joinder references (e.g., attached, coupled, connected, and the like) are to be construed broadly and may include intermediate members between a connection of elements and relative movement between elements. As such, joinder references do not necessarily infer that two elements are directly connected and in fixed relation to each other. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative, only and not limiting. Changes in detail or structure may be made without departing from the spirit of the invention as defined in the appended claims.