Five degree of freedom ultrasound catheter and catheter control handle

Catheter ultrasound systems including a sheath, a handle, a sheath lumen, and an ultrasound catheter disposed within the lumen of the sheath with ultrasound elements capable of visualizing anatomical regions. The handle allowing the ultrasound catheter to rotate with respect to the sheath using a rotation adjustment knob within the handle or alternatively an separate manipulation handle attached to the proximal end of the ultrasound catheter. The sheath, ultrasound catheter, or both may also include one or more electrodes or other location sensor for both orienting the ultrasound element as well as for diagnostic purposes.

BACKGROUND OF THE INVENTION

a. Field of the Invention

The present invention relates to ultrasound catheters and sheaths and methods of using ultrasound catheters and sheaths. More particularly, the present invention relates to a control handle for steerable sheaths, methods of manufacturing and using such a handle, an ultrasound catheter for use with the steerable sheath, and methods of using the combination of the ultrasound catheter and sheath.

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 invasive 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'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's control handle, which remains outside the patient'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.

Prior art control handles are often inadequate with respect to their ability to provide the finely controlled deflection adjustment for the distal end of the catheter body necessary to target a particular anatomy with an ultrasound catheter. The prior art control handles often provide inadequate deflection wire travel for a desired viewing angle or orientation. 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. Moreover, it is desirable that the physician be able to set the ultrasound catheter at a particular viewing angle and have it stay set. However, with prior art catheters the control handles typically require the physician to take a conscious step to maintain the catheter at the desired deflection.

One type of instrument catheter is an ultrasound visualization catheter, such as an intracardiac echocardiography (ICE) catheter, which includes ultrasound elements or arrays on the distal end of the catheter. The ultrasound elements are useful for visualizing particular portions of the cardiac anatomy under study. The typical ultrasound catheter aims a two dimensional beam or fan at a portion of the anatomy and provides the clinician with a visual of the anatomy under study. Because the fan may be both narrow and small, and of limited range, precise adjustments are often necessary in order to successfully view particular anatomy. Thus, the ability to adjust the orientation or direction of an ultrasound fan precisely, with minimal or no deformation of the catheter, is important in using an ultrasound catheter. Providing a handle with fine motor control and a desirable mechanical advantage also has specific utility for an ultrasound catheter. In particular, there is a need in the art for a catheter system that offers improved operation and deflection adjustment of the distal end of the ultrasound catheter body. There is also a need in the art for a method of manufacturing and using such a catheter system.

BRIEF SUMMARY OF THE INVENTION

A catheter system may include a fixed dimensional and bi-directional steerable catheter control handle having 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 member may include proximal and distal end portions, with the proximal end portion being coupled to the handle grip. An actuator 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 deflection wires may be operably coupled to the actuator and to the distal end portion of the flexible member such that rotation of the actuator imparts a tensile force to the deflection wires thereby causing the distal end portion of the flexible member to deflect from a prior configuration while maintaining the generally predetermined exterior dimensions of the handle grip and the actuator.

For the system described above, in an embodiment, the system may include means for simultaneously imparting a tensile force to the first deflection wire and releasing a tensile force on the additional deflection wire. The actuator 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 actuator may impart opposing forces to the axially displaceable members.

For the apparatus described above, in an embodiment, the flexible body may include one or more longitudinal lumens. In an embodiment, the apparatus may include one or more electrodes coupled to the flexible body. The flexible body, 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 flexible member. The reinforcing element may include braided members, which may include a conductive material.

For the apparatus described above, in an embodiment, the flexible body 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 actuator may include a generally longitudinal groove and/or a generally longitudinal protuberance.

In one embodiment, the invention comprises an ultrasound catheter system including a sheath or guiding catheter having a flexible body with a lumen running completely through it. The flexible body having a distal end connected to one or more deflection wires and a proximal end portion coupled to a handle. The handle comprising a actuator, a second actuator and a handle grip with a lumen running completely through the handle that, combined with the lumen of the guiding catheter, creates a continuous lumen from the guiding catheter's distal end to the proximal end of the handle. In some embodiments the actuators are adjustment knobs capable of pivoting about the longitudinal axis of the handle. The handle also contains a plurality of slides attached to the deflection wires of the guiding catheter. The slides being disposed such that rotation of the first actuator causes the deflection members to displace axially within the handle grip placing at least one deflection wire in tension thereby deflecting the distal end of the guiding catheter. The handle also contains a rotation assembly operably connected to the second actuator.

An instrument catheter having an elongate body with a instrument element attached to its distal end, such as an ICE catheter, can be disposed within the continuous lumen such that the instrument element extends beyond the distal end of the guiding catheter and the proximal portion of the elongate body is attached to the rotation assembly. In one embodiment, the instrument element can be an ultrasound element, such as a linear phased array. In another embodiment, the instrument element can be a therapeutic instrument, such as an ablation element. The instrument catheter can be a diagnostic catheter, such as an ultrasound catheter, or a therapeutic catheter, such as an ablation catheter.

Rotation of the second actuator about the longitudinal axis causes the rotation assembly to rotate the instrument catheter about the longitudinal axis. In an embodiment, the rotation assembly rotates the instrument catheter through the same angular displacement as the second actuator is rotated. In another embodiment, the rotation assembly rotates the instrument catheter in the same direction about the longitudinal axis as the second actuator is rotated. In yet another embodiment, the rotation assembly includes a drive gear operably connected to the second actuator, one or more ratio gears that transmit torque received by the drive gear from the second actuator to a positioning gear. The positioning gear being coupled to the proximal end portion of the instrument catheter, thereby causing the instrument catheter to rotate with the positioning gear. In another embodiment, the rotation assembly may contain a tube attached to the positioning gear that passes through the rotation assembly as part of the continuous lumen. In such an embodiment, a instrument catheter may be attached to the inner surface of the tube to cause it to rotate with the tube in response to the rotation of the second actuator.

In one embodiment, the distal end portion of the instrument catheter contains one or more location sensors, such as electrodes or magnetic coils to aid in the location and orientation of the distal end portion. In another embodiment, the location sensors may be operably connected to an electroanatomical mapping system.

In another embodiment, the handle can include an irrigation lumen coupled to the proximal end of the guiding catheter that maintains a fluid relationship with the lumen of the guiding catheter.

DETAILED DESCRIPTION OF THE INVENTION

Referring toFIG. 1, one embodiment of the present invention having a control handle2for a flexible tubular body4of a catheter5is depicted in an isometric view. Throughout this specification, the term catheter is meant to include, without limitation, catheters, sheaths and similar medical devices. As shown inFIG. 1, in one embodiment of the present invention, the distal end of the handle2is connected to the catheter body4and the proximal end of the handle2is connected to tubing6that contains electrical wire and extends to an electrical connector8. The handle2includes an actuator10depicted as an adjustment knob and a handle grip12. For clarity, the actuator10will be referred to as an adjustment knob, but the actuator10may also be a dial, lever, switch, or other device for receiving input from a user without departing from the spirit and scope of the invention. As will become clear from this specification, the handle2of the present invention is advantageous in that it is compact and allows a user to manipulate the catheter body's extreme distal end14is a bi-directional manner by pivoting the adjusting knob10relative to the handle grip12in one direction or the other about the longitudinal axis of the handle2. Furthermore, in one embodiment, the handle2has a lumen that runs uninterrupted from the proximal end of the handle2to the extreme distal end14of the catheter body4. This lumen can be used to provide contrast injection for guide wire insertion.

For a more detailed discussion of the handle2, reference is now made toFIGS. 2 and 3.FIG. 2is an isometric view of handle2exploded to show its various components.FIG. 3is a longitudinal sectional elevation of the handle2taken along section line AA ofFIG. 1.

As shown inFIGS. 2 and 3, the adjusting knob10is pivotally attached to a mounting shaft (i.e., a slide base or base portion)16contained within the handle grip12. To pivotally attach the knob10to the mounting shaft16, a dowel pin18is inserted into a pinhole20in the distal end of the shaft16and mates with a groove22in a hub portion23of the knob10. A silicone o-ring24exists between the hub portion23of the knob10and the distal end of the shaft16.

As indicated inFIGS. 2 and 3, a wire guide26is positioned within the adjusting knob10and is held in place by a retaining ring28. A right slide or member30and a left slide or member32are slideably positioned within a slot (i.e., a slide compartment)34in the mounting shaft16. A catheter body-retaining nut36is used to secure the catheter body4to the distal end of the wire guide26.

As illustrated inFIG. 3, a pair of deflection wires38extend from the extreme distal end14of the body4, through the body4, the wire guide26and a passage40formed between the two slides30,32, to a point near a proximal portion of the slides30,32. Each wire38then affixes to an individual slide30,32via a retention screw42.

For a more detailed discussion of the slides30,32and their relationship to the deflection wires38, reference is now made toFIG. 4, which is an isometric view of the deflection wires38a,38battached to the right and left slides30,32. As shown inFIG. 4, the slides30,32, which are mirror images of each other, each have a rectangular box-like proximal portion44and a half-cylinder distal portion46. Each proximal portion44has a generally planar sides and bottom of the slot34, which act as thrust surfaces for the slides30,32.

Each half-cylinder distal portion46is hollowed out along its longitudinal axis to form the passage40through which the deflection wires38a,38band, as indicated inFIG. 3, the narrow proximal portion of the wire guide26extend when the slides30,32are in the assembled handle2. Each slide30,32has a planar slide face48that is meant to slideably abut against the planar slide face48of the opposing slide30,32. Thus, as illustrated inFIG. 2, when the planar slide faces48of the slides30,32abut against each other and the extreme proximal ends of each slide30,32are flush with each other, the half-cylinder distal portions46of each slide30,32combine to form a complete cylinder with a channel or passage40there through.

As shown inFIG. 4, in one embodiment, the proximal ends of each deflection wire38a,38bforms a loop50through which a retention screw42passes to secure the wire38a,38bto the proximal portion of the respective slide30,32. As indicated inFIG. 5, which is a side elevation of an exemplary slide30, in one embodiment, the proximal end of each deflection wire38forms a knot52. The wire38passes through a hollow tension adjustment screw54and the knot52abuts against the head55of screw54, thereby preventing the wire38from being pulled back through the screw54. In one embodiment, the screw's longitudinal axis and the longitudinal axis of the slide30,32are generally parallel. Each tension adjustment screw54is threadably received in the proximal end of its respective slide30,32. Tension in a wire38may be increased by outwardly threading the wire's tension adjustment screw54. Conversely, tension in a wire38may be decreased by inwardly threading the wire's tension adjustment screw54.

As can be understood fromFIG. 4, in one embodiment where the wires38a, and38bare intended to only transmit tension forces, the wires38a,38bmay deflect or flex within an open area45defined in the proximal portion44of each slide30,32when the slides30,32displace distally. Similarly, as can be understood fromFIG. 5, in another embodiment where the wires38are intended only to transmit tension forces, the wires38may slide proximally relative to the screw54when the slides30,32displace distally.

As shown inFIG. 4, in one embodiment, the outer circumference of the half-cylinder distal portion46of the right slide30is threaded with a right-hand thread56, and the outer circumference of the half-cylinder distal portion46of the left slide32is threaded with a left-hand thread58. In one embodiment, the outer circumference of the half-cylinder distal portion46of the right slide30is threaded with a left-hand thread, and the outer circumference of the half-cylinder distal portion46of the left slide32is threaded with a right-hand thread.

For a better understanding of the relationship of the slide threads56,58to the rest of the handle2, reference is now made toFIG. 6, which is a longitudinal sectional elevation of the adjusting knob10taken along section line AA ofFIG. 1. As indicated inFIG. 6, a cylindrical hole or shaft60passes through the knob10along the knob's longitudinal axis. In the hub portion23of the knob10, the inner circumferential surface of the shaft60has both right hand threads62and left hand threads64. These internal threads62,64of the knob10mate with the corresponding external threads56,58of the slides30,32. More specifically, the right internal threads62of the knob10mate with the right external threads56of the right slide30, and the left internal threads64of the knob10mate with the left external threads58of the left slide32.

Thus, as can be understood fromFIGS. 2,3,4, and6, in one embodiment, as the knob10is rotated clockwise relative to the longitudinal axis of the handle2, the internal and external right threads62,56engage and the internal and external left threads64,58engage, thereby causing simultaneous opposed displacement of the right and left slides30,32longitudinally within the slot34in the handle10. Specifically, because of the threading arrangement of the knob10and the slides,30,32, the right slide30moves distally within the slot34and the left slide32moves proximally within the slot34when the knob10is rotated clockwise relative to the handle grip12of the handle2. Conversely, when the knob10is rotated in a counterclockwise manner relative to the handle grip12of the handle2, the right slide30moves proximally within the slot34and the left slide32moves distally within the slot34.

As can be understood fromFIGS. 4 and 6, when the knob10is rotated such that the right slide30is urged distally and the left slide32is urged proximally, the deflection wire38aconnected to the right slide30is placed into compression and the deflection wire38bconnected to the left slide32is placed into tension. This causes the extreme distal end14of the catheter body4to deflect in a first direction. Conversely, when the knob10is rotated such that the right slide30is urged proximally and the left slide32is urged distally, the deflection wire38aconnected to the right slide30is placed into tension and the deflection wire38bconnected to the left slide32is placed into compression. This causes the extreme distal end14of the catheter body4to deflect in a second direction that is opposite the first direction.

The control handle2of the present invention as described has several advantages. First, the handle2is compact and may be operated with a single hand, allowing the clinician to keep a second hand free or on a second device. Second, the threaded slides30,32and knob10allow a physician to make fine, controlled adjustments to the bend in the distal end14of the catheter body4. Third, once the knob1- is rotated so as to cause a bend in the distal end14of the catheter body4, the threads56,58,62,64interact to maintain the bend without requiring any action on the physician's part. Fourth, because the slides30,32simply displace distally and proximally along the longitudinal axis of the handle2, they are less likely to permanently deform the wires38as compared to the wire displacement mechanisms in some prior art handles. Fifth, the threads56,58,62,64are mechanically advantageous in that they provide increased deflection wire travel and reduced actuation effort for the physician, as compared to some prior art handles.

WhileFIGS. 2-6depict an embodiment where the slides30,32have external threads56,58and the knob10has internal threads62,64, in other embodiments the threading arrangement is reversed. For a discussion of one such embodiment, reference is made toFIGS. 33-35.FIG. 33is a longitudinal sectional elevation of the handle2taken along section line AA ofFIG. 1.FIG. 34is a side elevation of an exemplary slide employed in the embodiment depicted inFIG. 33.FIG. 35is a longitudinal sectional elevation of the adjusting knob taken along section line AA ofFIG. 1.

A comparison of the embodiment depicted inFIGS. 33-35to the embodiment depicted inFIGS. 3,5, and6reveals that the two embodiments are generally the same, except as will be described in the following discussion ofFIGS. 33-35. Reference numbers utilized inFIGS. 33-35pertain to the same or similar features identified by the same reference numbers inFIGS. 3,5, and6.

As shown inFIG. 33, the adjusting knob10is pivotally attached to a mounting shaft (i.e., a slide base or base portion)16contained within the handle grip12. A wire guide26is positioned within the adjusting knob10. like the embodiment depicted inFIG. 2, the embodiment illustrated inFIG. 33includes a right slide or member30and a left slide or member32that are slideably positioned within a slot (i.e., a slide compartment)34in the mounting shaft16.

As can be understood fromFIG. 34, the slides30,32, which are mirror images of each other, each have a rectangular box-like proximal portion44and a distal portion46that may be rectangular or half-cylindrical. Each proximal portion44has a generally planar outer sidewall and bottom wall. These planar surfaces slideably displace against the generally planar sides and bottom of the slot34, which act as thrust surfaces for the slides30,32.

Each distal portion46is hollowed out to form half of a cylindrical passage40that is created when the slides30,32are abutted against each other in a side-by-side relationship. Thus, each distal portion46of each slide30,32includes an inner circumferential surface, which when combined with the inner circumferential surface of the other slide30,32, defines the cylindrical passage40.

As indicated inFIG. 34, in one embodiment, the inner circumferential surface of the right slide30is threaded with a right-hand thread56. Similarly, as can be understood fromFIG. 34, the inner circumferential surface of the left slide32is threaded with a left-hand thread58. Thus, the distal portion46of each slide30,32is equipped with internal threads. In another embodiment, the inner circumferential surface of the right slide30is threaded with a left-hand thread58. Similarly, the inner circumferential surface of the left slide32is threaded with a right-hand thread56.

As indicated in35, the knob10includes an outer hub23asurrounding an inner hub23b. A space65exists between, and is defined by, the inner and outer hubs23a,23b. The space65is adapted to receive the distal ends46of each slide30,32. The outer circumferential surface of the inner hub23bhas both right hand threads62and left hand threads64. These external threads62,64of the knob10mate with the corresponding internal threads56,58of the slides30,32. More specifically, the right external threads62of the knob10mate with the right internal threads56of the right slide30, and the left external threads64of the knob10mate with the left internal threads58of the left slide32.

As can be understood fromFIG. 33, in one embodiment, as the knob10is rotated clockwise relative to the longitudinal axis of the handle2, the internal and external right threads56,62engage and the internal and external left threads58,64engage, thereby causing simultaneous opposed displacement of the right and left slides30,32longitudinally within the slot34in the handle10. Specifically, because of the threading arrangement of the knob10and the slides,30,32, the right slide30moves distally within the slot34and the left slide32moves proximally within the slot34when the knob10is rotated clockwise relative to the handle grip12of the handle2. Conversely, when the knob10is rotated in a counterclockwise manner relative to the handle grip12of the handle2, the right slide30moves proximally within the slot34and the left slide32moves distally within the slot34.

As can be understood fromFIG. 33, when the knob10is rotated such that the right slide30is urged distally and the left slide32is urged proximally, the deflection wire38connected to the right slide30is placed into compression and the deflection wire38connected to the left slide32is placed into tension. This causes the extreme distal end14of the catheter body4to deflect in a first direction. Conversely, when the knob10is rotated such that the right slide30is urged proximally and the left slide32is urged distally, the deflection wire38connected to the right slide30is placed into tension and the deflection wire38connected to the left slide32is placed into compression. This causes the extreme distal end14of the catheter body4to deflect in a second direction that is opposite the first direction.

For a detailed discussion of another embodiment of the handle2of the present invention, reference is now made toFIGS. 7,8, and9.FIG. 7is a plan view of the handle2.FIG. 8is a side elevation of the handle2.FIG. 9is an isometric view of the distal end of the handle2.

As shown inFIGS. 7-9, the handle2includes an adjusting knob10on its distal end and a handle grip12on its proximal end. As can be understood fromFIGS. 7-9, in one embodiment, the knob10has a generally circular cross-section and the handle grip12has a generally oval cross-section. In one embodiment, both the knob10and the handle grip12have generally circular cross-sections. The oval cross-section of the handle grip12is advantageous because it provides the physician with a tactile indication of the catheter's rotational position.

For a more detailed discussion f the components of the handle2, reference is now made toFIG. 10, which is a longitudinal sectional plan view of the handle2taken along section line BB ofFIG. 9. As shown inFIG. 10, an o-ring24is located between the handle grip12and a groove in the knob10. The knob10is pivotally affixed to the handle grip12via a rotating retaining-ring60that resides within grooves in both the knob and the handle grip12.

As illustrated inFIG. 10, a catheter body-retaining nut36is threadably affixed to the distal end of a wire guide26that extends along the axial center of the knob10. As indicated inFIG. 10and more clearly shown inFIG. 11, which is a longitudinal sectional plan view of the knob10taken along section line BB inFIG. 9, a cylindrical hole or shaft60passes through the knob10along the knob's longitudinal axis. The inner circumferential surface of the shaft60has both right hand threads62and left hand threads64that extend towards the distal end of the knob10from a hub portion23of the knob10. As shown inFIG. 11, in one embodiment, the knob10is a singular integral piece.

As indicated inFIG. 10, a right slide30and a left slide32are longitudinally displaceable within the handle2and about the proximal end of the wire guide26. As shown inFIGS. 12 and 13, which are, respectively, a right side isometric view of the slides30,32displaced about the wire guide26and a left side isometric view of the slides30,32displaced about the wire guide26and a left side isometric view of the slides30,32displaces against the slide face48of the opposed slide30,32to form a passage40through which the proximal end of the wire guide26passes as the slides30,32displace about the wire guide26. As shown inFIG. 10, the passage40formed by the channels40also provides a pathway along which the deflection wires38a,38b(represented by a dashed line inFIG. 10) travel from a proximal portion of the slides30,32, through the wire guide26, and onward to the extreme distal end14of the catheter body4.

As indicated inFIGS. 12 and 13, each slide30,32has a half-cylinder distal portion46and a shorter and wider half-cylinder proximal portion47. The right slide30has a right-handed thread56on its distal portion46. Similarly, the left slide32has a left-handed thread58on its distal portion46. Thus. As can be understood fromFIG. 10, when the knob10is rotated in a clockwise direction relative to the handle grip12, the right handed threads62within the knob10engage the right handed threads56of the right slide30, and the left handed threads64within the knob10engage the left handed threads56of the left slide32. As a result, the right slide30is distally displaced within the handle2and the left slide32is proximally displaced within the handle2. Accordingly, the deflection wire38aattached to the right slide30is pushed (i.e., subjected to a compressive force) and the deflection wire38battached to the left slide32is pulled (i.e., subjected to a tension force). Conversely, if the knob is rotated counterclockwise, the opposite displacement of the slides30,32and deflection wires38a,38bwill occur.

As indicated inFIG. 10, each deflection wire38a,38bis attached to the proximal portion47of its respective slide30,32via retention screws42. the retention screws, which are more clearly illustrated inFIGS. 12 and 13are threadably mounted in the proximal portions47.

As shown inFIGS. 12 and 13, each half-cylindrical proximal portion47of a slide30,32has an upper and lower planar notch64adjacent their respective planar slide faces47. The function of these notches64may be understood by referring toFIGS. 14 and 15.

FIG. 14is a longitudinal section elevation of the handle grip12taken along section line CC inFIG. 7.FIG. 15is a latitudinal section elevation of the handle grip12taken along section line DD inFIG. 8. As shown inFIGS. 14 and 15, the handle grip12is one integral piece having an interior cylindrical void66in which the proximal portions47of the slides30,32may displace as indicated inFIG. 10.

As shown inFIGS. 14 and 15, upper and lower ribs68extend from the walls that form the interior cylindrical void66. the ribs68run longitudinally along a substantial portion of the cylindrical void's length. As can be understood fromFIGS. 12-15, the upper planar notches64on the proximal portions47of the slides30,32interface with, and displace along, the upper rib68as the slides30,32displace within the cylindrical void66. Similarly, the lower planar notches64on the proximal portions47of the slides30,32interface with, and displace along, the lower rib68as the slides30,32displace within the cylindrical void66. Thus, the ribs68act as thrust surfaces for the slides30,32.

For a detailed discussion of another embodiment of the handle2depicted inFIGS. 7-15, reference is now made toFIG. 16.FIG. 16is an isometric view of the distal end of a control handle2for a catheter5wherein the handle2and catheter body4have a through lumen70. As shown inFIG. 16, in one embodiment, the lumen70and the electrical wire tube6, which extends to the electrical connector8, pass through strain reliefs71and into the proximal end of the handle grip12. in one embodiment, the lumen70terminates at its proximal end with a stopcock72. In one embodiment, the stopcock72has a hemostasis seal74that can be utilized for guide wire insertion. While a long flexible length of lumen70, as depicted inFIG. 16, provides motion isolation while inserting contrast from a syringe, in one embodiment, the lumen70does not extend from the handle grip12. Instead, the stopcock72or luer fitting is simply attached to the lumen70where it exits the proximal end of the handle grip12.

For a better understanding of the path of the lumen70, reference is now made toFIGS. 17,18, and19.FIG. 17is an isometric view of the slides30,32, the wire guide26, the wire tubing6, and the lumen70illustrating the path the lumen70takes through the handle2.FIG. 18is an elevation view of the extreme proximal end surfaces of the slides30,32as viewed from arrow A inFIG. 17and illustrating the path the lumen70and wire tubing6take into the passage40formed by the channels40of the slides30,32.FIG. 19is an isometric view of the lumen70, deflection wires38a,38b, and electrical wires76of the wire tube6exiting the catheter body-retaining nut36on the distal end of the handle2.

As shown inFIGS. 17 and 18, the lumen70and the wire tubing6pass through their respective reliefs71and into the passage40formed by the channels40in each slide30,32. In one embodiment, soon after the wire tubing6and the lumen70enter the passage40, the wires76of the wire tubing6exit the wire tubing6and are dispersed about the outer circumference of the lumen70as depicted inFIG. 19.

As illustrated inFIG. 17, in another embodiment, after the wire tube6and lumen70enter the passage40, the wire tube6and the lumen70continue on their pathway to the distal end14of the catheter body4by passing, in a side-by-side arrangement, through the remainder of the passage40formed into the slides30,32and into an internal passage that extends along the longitudinal axis of the wire guide26. near the end of the wire guide26, the wire76exits the wire tube6. The wire76, lumen70and deflection wires38a,38bthen pass into the catheter by exiting the catheter body-retaining nut36of the handle as indicated inFIG. 19.

For a detailed discussion of another embodiment of the handle2, reference is now made toFIG. 20, which is an isometric view of the handle2exploded to show its various components. As can be understood fromFIG. 20, the features of the handle2depicted inFIG. 20is configured to have a relatively large, generally uniform in diameter, pathway extend the full length of the handle2(i.e., from the distal opening102in the wire guide26, through the passage40defined in the slides30,32and through an exit hole104in the proximal end of the shaft16).

The configuration of the handle2that allows a relatively large generally uniform in diameter pathway to pass through the length of the handle2, as depicted inFIG. 20, is more clearly shown inFIG. 21, which is a longitudinal sectional elevation taken along section line ZZ inFIG. 20. As illustrated inFIG. 21, in one embodiment, the pathway100, which includes the passage through the wire guide26and the passage40through the slides30,32, is large enough that the catheter body4itself may pass through the pathway100and be connected to the proximal end of the shaft16at the exit hole104. Thus, in one embodiment, to prevent the catheter body4from rotating with the adjusting knob10, the catheter body4is affixed to the shaft16at the exit hole104. In one embodiment, the catheter body4runs the full length of the handle4as depicted inFIG. 21, except the body4is affixed to the wire guide26at or near the distal opening102. In other embodiments, the catheter body4is affixed to both the wire guide26at or near the distal opening102and the shaft16at the exit hole104.

As can be understood fromFIG. 21and as more clearly depicted inFIG. 22, which is isometric views of the slides30,32oriented to show their portions of the passage40and their planar slide faces48, the passage40is large enough in diameter to displace over the outer diameter of the wire guide26. As shown inFIGS. 21 and 22, a catheter body passage110passes through the proximal portion44of each slide30,32, thereby allowing the slides30,32to displace back and forth over the outer surface of the catheter body4.

As indicated inFIG. 21, in one embodiment, the catheter body4has an opening111in its wall that allows the wires38to exit the body4and connect to the slides30,32. In one embodiment, the wires38connect to the slides30,32via tension adjustments screws54as previously discussed.

Due to the configuration of the slides30,32, the wire guide26and the shaft16, the catheter body4may run uninterrupted the full length of the handle2. As a result, electrical wiring76(seeFIG. 19) and a lumen70may be routed the full length of the handle2by way of the body4.

For a detailed discussion of another embodiment of the handle2of the present invention, reference is now made toFIGS. 23 and 24.FIG. 23is an isometric view of the handle2exploded to show its various components.FIG. 24is a longitudinal sectional elevation of the handle2taken along section line YY ofFIG. 23. Generally speaking, the features of the handle2depicted inFIGS. 23 and 24are similar to the features of the handle depicted inFIG. 20, except the two embodiments employ different slider arrangements. For example, the embodiments depicted inFIGS. 1-22employ parallel slides or members30,32(i.e., the slides30,32exist within the handle2in a parallel or side-by-side arrangement). As will be understood fromFIGS. 23 and 24and the following figures, in the embodiment of the handle2depicted inFIGS. 23 and 24, the slides or members150,152exist within the adjustment knob10in a series arrangement (i.e., the slides150,152are not parallel or side-by-side to each other, but are oriented end-to-end along a longitudinal axis of the handle2).

As shown inFIGS. 23 and 24, the adjusting knob10is pivotally coupled to the distal end of the mounting shaft (i.e., base portion)16. The wire guide26extends through the center of the adjusting knob10and the mounting shaft16. The catheter body4is coupled to the distal end of the wire guide26and, in one embodiment, extends through the wire guide26and out of the proximal end of the mounting shaft16.

As shown inFIGS. 23 and 24, a distal slide150is located in a distal portion of the adjusting knob10, and a proximal slide152is located in a proximal portion (i.e., hub portion23) of the adjusting knob10. As illustrated inFIG. 24, the outer surface of each slide150,152has threads154that mate with threads156on an interior surface of the adjusting knob10.

As illustrated inFIG. 24, each deflection wire38a,38btravels along the interior of the wire guide26until it exits the wire guide26at a hole157in the sidewall of the wire guide26. Each deflection wire38a,38bthen extends to the slide150,152, to which the deflection wire38a,38bis attached. In one embodiment, in order to attach to a slide150,152, a deflection wire38a,38bpasses through a passage159in the slide150,152and attaches to a hollow tension adjustment screw54via a knot52as previously described in the Detailed Description.

For a better understanding of the orientation of the threads154,156, reference is now made toFIGS. 25 and 16.FIG. 25is the same longitudinal sectional elevation of the adjusting knob10as it is depicted inFIG. 24, except the adjusting knob10is shown by itself.FIG. 26is a side elevation of the slides150,152.

As shown inFIGS. 25 and 26, in one embodiment, the distal slide150has right hand threads154that engage right hand threads156in the distal portion of the adjusting knob10, and the proximal slide152has left hand threads154that engage the left hand threads156in the proximal portion of the adjusting knob10. Thus, as can be understood fromFIGS. 23-26, when the adjusting knob10is relative to the mounting shaft16in a first direction about the longitudinal axis of the handle2, the slides150,152will converge along the wire guide26, thereby causing the first wire38to be placed into tension and the second wire38to be compressed. As a result, the distal end14of the catheter body4will deflect in a first direction. Similarly, when the adjusting knob10is rotated in a second direction that is opposite from the first direction, the slides150,152will diverge along the wire guide26, thereby causing the first wire38to be compressed and the second wire38to be placed into tension. As a result, the distal end14of the catheter body4will deflect in a second direction generally opposite from the first direction.

In one embodiment, to prevent the slides150,152from simply rotating around the wire guide26when the adjusting knob10is rotated, the slides150,152and wire guide26are configured such that the slides150,152will displace along the wire guide16, but not rotationally around it. For example, as indicated inFIG. 27A, which is a latitudinal sectional elevation of the handle2as taken along section line XX inFIG. 24, the wire guide26has a square cross section that mates with a square hole162running the length of the slide,150,152. The interaction between the square hole162and the square cross section of the wire guide26prevents a slide150,152from rotating about the wire guide26, but still allows the slide150,152to displace along the length of the wire guide26.

In another embodiment, as shown inFIG. 27B, which is the same latitudinal sectional elevation depicted inFIG. 27A, each slide150,152has a hole162with a circular cross section. Each hole162runs the length of its respective slide150,152and includes a key160that extends into hole162from the interior circumferential surface of the hole160. The key160engages a groove or slot158that runs along the length of the wire guide26as depicted inFIG. 28, which is a side elevation of one embodiment of the wire guide26. The interaction between the key160and the slot158prevents a slide150,152from rotating about the wire guide26, but still allows the slide150,152to displace along the length of the wire guide26.

As shown inFIGS. 27A and 27B, a hollow shaft165extends through the wire guide26. This allows a catheter body4with a lumen to extend completely through the handle2as shown inFIG. 24.

For a detailed discussion of another embodiment of the handle2that is similar to the embodiment depicted inFIG. 23, reference is now made toFIGS. 29 and 30.FIG. 29is a longitudinal sectional elevation of the handle2as if taken through section line VV inFIG. 23and wherein section line VV forms a plane that is perpendicular to the plane formed by section line YY inFIG. 23.

As illustrated inFIGS. 29 and 30, the handle2includes an adjusting knob10pivotally coupled to the distal end of the mounting shaft (i.e., base portion)16. In one embodiment, the adjusting knob10includes a proximal end170, a distal end172and a threaded shaft173, which is connected to the proximal end170and extends distally along the longitudinal axis of the adjusting knob10. The threaded shaft173includes a distal end174, a proximal end176, a series of right hand threads178along a distal portion of the shaft173, and a series of left hand threads180along a proximal portion of the shaft173.

As shown inFIGS. 29 and 30, a distal slide150is located in a distal portion of the adjusting knob10, and a proximal slide152is located in a proximal portion (i.e., hub portion23) of the adjusting knob10. Each slide has a hole155through which the threaded shaft173passes. The inner circumferential surface of the hole155for the distal slide150has right hand threads that mate with the right hand threads178on the distal portion of the shaft173. Similarly, the inner circumferential surface of the hole155for the proximal slide152has left hand threads that mate with the left hand threads180on the proximal portion of the shaft173. In other embodiments, the locations for the left and right threads are reversed.

As can be understood fromFIGS. 29,30, and31, which is an isometric view of one embodiment of the wire guide26, a hollow center shaft182extends from the distal end of the wire guide26, through the threaded shaft173of the adjustment knob10, and to the proximal end of the base shaft16. Thus in one embodiment, a catheter body4may be routed through the lumen165of the wire guide's hollow center shaft182to exit the proximal end of the handle2, as illustrated inFIGS. 29 and 30.

As illustrated inFIG. 29, each deflection wire38a,38btravels along the interior of the wire guide26until it exits the wire guide26at a hole157in the sidewall of the wire guide26. Each deflection wire38a,38bthen extends to the slide150,152to which the deflection wire38a,38bis attached. In one embodiment, in order to attach to a slide150,152, a deflection wire38a,38bpasses through a passage159in the slide150,152and attaches to a hollow tension adjustment screw54via a knot52as previously described in the Detailed Description.

In one embodiment, as shown inFIG. 29, the deflection wire38bleading to the proximal slide152passes through a second passage161in the distal slide150. The second passage161has sufficient clearance that the passage161may easily displace along the wire38bwhen the distal slide150displaces distally and proximally. The second passage161serves as a guide that stiffens the wire38band helps to reduce the likelihood that the wire38bwill bend when compressed.

As can be understood fromFIGS. 29 and 30, when the adjusting knob10is rotated relative to the mounting shaft16in a first direction about the longitudinal axis of the handle2, the slides150,152will converge along the threaded shaft173, thereby causing the first wire38ato be placed into tension and the second wire38bto be compressed. As a result, the distal end14of the catheter body4will deflect in a first direction. Similarly, when the adjusting knob10is rotated in a second direction that is opposite from the first direction, the slides150,152will diverge along the threaded shaft173, thereby causing the first wire38ato be compressed and the second wire38bto be placed into tension. As a result, the distal end14of the catheter body4will deflect in a second direction generally opposite from the first direction.

In one embodiment, to prevent the slides150,152from simply rotating with the threaded shaft173within the adjusting knob10when the adjusting knob10is rotated, the slides150,152and wire guide26are configured such that the slides150,152will displace along the threaded shaft173, but not rotationally within the adjusting knob10. For example, as indicated inFIGS. 31 and 32, which is a latitudinal sectional elevation of the handle2as taken along section line WW inFIG. 29, the wire guide26has right and left semicircular portions190that oppose each other and extend along the length of the hollow center shaft182of the wire guide26. As shown inFIG. 32, the generally planar opposed faces192of the semicircular portions190abut against the generally planar side faces194of the slides150,152. This interaction prevents a slide150,152from rotating within the adjustment knob10when the knob10is rotated, but still allows the slide150,152to displace along the length of the threaded shaft173.

In an another embodiment, the handle2allows a user to manipulate the extreme distal end14of a catheter body4having a lumen extending completely therethrough in a bi-directional manner by pivoting a first adjusting knob10arelative to handle grip12in one direction or the other about the longitudinal axis of the handle2, and allows the user to rotate an instrument catheter196disposed within the lumen of the catheter body4by pivoting a second adjusting knob10brelative to the handle grip12about the longitudinal axis of handle2. For clarity, the instrument catheter196will be referred to as an ultrasound catheter, but the instrument catheter196may also be a therapeutic catheter, such as an ablation catheter, or another type of diagnostic catheter without departing from the spirit and scope of the invention. The ultrasound catheter196is disposed in a coaxial relationship within the lumen of the catheter body4allowing a the bidirectional manipulation of the catheter5to cause a corresponding deflection in the ultrasound catheter196. In this manner, catheter5acts as a guiding catheter for the ultrasound catheter196and allows a user to steer the ultrasound catheter196by deflecting the guiding catheter5.

Now referring theFIGS. 36-40, the adjusting knob10ais pivotally attached to mounting shaft16contained within handle grip12. The adjusting knob10ais attached to mounting shaft16with a dowel pin18that is inserted into a pinhole20ain the distal end of the shaft16that mates with a groove22in a hub portion23of the knob10a. The groove22allows adjusting knob10ato pivot freely around the longitudinal axis of mounting shaft16while contact between the walls of groove22and dowel pin18constrain adjusting knob10afrom moving axially along the longitudinal axis of mounting shaft16. A right slide30and a left slide32are positioned within slot34of the mounting shaft16.

Now referring toFIGS. 36 and 37, slides30,32have a generally rectangular box-like proximal portion44and a half-cylinder distal portion46. Each proximal portion44has a generally planar sides that contact the walls of slot34.

Each slide30,32has a planar face48extending from the distal portion46to the proximal portion44that is meant to slideably abut against the planar face48of the opposing slide30,32. The planar face48of each slide30,32is hollowed out along its longitudinal axis to form a passage40through which the guiding catheter5and its deflection wires38a,38bas well as the ultrasound catheter196pass. The proximal portion44of slides30,32have a slot198through which deflection wires38a,38bpass. The defection wires38a,38bare retained in slot198using a dowel pin (not shown) inserted in hole200, and deflection wires38a,38bare constrained axially by a wire lock nut (not shown) attached, for example, by soldering to deflection wires38a,38b. The proximal portion of the left slide32contains a notch204that allows a drive shaft206to extend from the proximal end of the slot34distally to the second adjusting knob10b. In an alternative embodiment, the right slide30can contain a notch204to allow a drive shaft206to extend from the proximal end of the slot34distally to the second adjusting knob10b.

The outer circumference of the distal portion46of right slide30is threaded with a right-hand thread56, and the outer circumference of the half-cylinder distal portion46of the left slide32is threaded with a left-hand thread58. In another embodiment, the outer circumference of the half-cylinder distal portion46of the right slide is threaded with a left-hand thread58, and the outer circumference of the half-cylinder distal portion46of the left slide32is threaded with a right-hand thread. When assembled in handle2the planar face48of each of the slides30,32abut and form a cylinder having right-hand thread56on one half of the outer surface of cylinder and left-hand thread58on the other half of the outer surface of the cylinder.

Now referring toFIGS. 36-39, the relationship of slides30,32to adjusting knob10awill be described. Adjusting knob10acontains a shaft60extending from the proximal end of hub23to the distal end of adjusting knob10athrough which guiding catheter5and ultrasound catheter196pass. A portion of shaft60is threaded with an internal right-hand thread and the same portion of shaft60is also threaded with an internal left-hand thread (not shown). The internal threads of the shaft60engage with threads56,58of the slides30,32. Thus, when the adjusting knob10ais rotated the internal and external right-hand threads56engage and the internal and external threads58engage and cause simultaneous opposed displacement of the right and left slides30,32longitudinally within slot34. The proximal portions44of each of slide30,32engages slot34so as to prevent slides30,32from rotating with adjusting knob10a.

The movement of slides30,32in opposite directions through the pivoting of adjusting knob10acauses the deflection wires38a,38bto be placed in a state of tension or compression. For example, when right slide30is disposed in a proximal direction in response to the pivoting of adjusting knob10athe deflection wire38aattached to the right slide30is pulled in a proximal direction causing wire38ato be placed in tension. Simultaneously, left slide32is disposed in a distal direction in response to the pivoting of adjusting knob10aand deflection wire38battached to the left slide32is pushed in a distal direction causing the wire38bto be placed in compression. When adjusting knob10ais pivoted in the opposite direction, right slide30is disposed distally placing deflection wire38ainto compression and left slide32is simultaneously disposed proximally placing deflection wire38binto tension.

Placing deflection wire38ain tension and deflection wire38binto compression by pivoting adjusting knob10ain a first direction causes the extreme distal end14of the guiding catheter5to deflect in a first direction. Conversely, placing deflection wire38ain compression an deflection wire38binto tension by pivoting adjusting knob10ain a second direction causes the extreme distal end of the guiding catheter5to deflect in a second direction. Guiding catheter5extends proximally through the shaft60of adjusting knob10a, through passage40of slides30,32, and terminates in a proximal end having a retaining nut36. The retaining nut36abuts against the distal face of gear assembly208and provides a hemostatic seal between the retaining nut36and gear assembly208. guiding catheter5is constrained within mounting shaft16by pillow block210. In one embodiment, the retaining nut36of guiding catheter5is flared such that it has an outer diameter greater than the outer diameter of the catheter body4. Pillow block210can be configured to have an internal surface configured to mate to the flared retaining nut36. In an alternative embodiment, the retaining nut36can have an annular ring extending perpendicular to the longitudinal axis of the guiding catheter5, which abuts against pillow block210to constrain guiding catheter5against the gear assembly208. Pillow block210is attached to mounting shaft16with dowel pins18inserted into pin holes20b,20c.

The retaining nut36of guiding catheter5may be configured to receive an irrigation lumen212. The irrigation lumen212allows the user to introduce an irrigation fluid into the guiding catheter5that prevents body fluids, such as blood, from entering the lumen70of the guiding catheter5. Irrigation fluid delivered through the irrigation lumen212provides lubrication between the ultrasound catheter196and the guiding catheter's5inner wall.

Ultrasound catheter196has a distal end214, a flexible tubular body216that may have a lumen extending therethrough, and a proximal end218. The distal end214has an ultrasound element220described in further detail below. The ultrasound body216extends from the distal end214to the gear assembly208within the lumen of the guiding catheter5. The ultrasound body216is not connected directly to the guiding catheter5and can freely rotate within the lumen. The ultrasound body216exits the guiding catheter5through its retaining nut36and extends into a hemostasis tube222. The hemostasis tube's222distal end is substantially coplanar with the distal face of the gear assembly208, and extends proximally through the gear assembly208to exit handle grip12at its proximal end. The hemostasis tube222passes through and is fixedly attached to a positioning gear224within the gear assembly208, which causes the hemostasis tube222to rotate with the positioning gear224. Thus, the lumen of the catheter5and the hemostasis tube222create a continuous lumen70extending from the distal tip14of the catheter5to the proximal end of handle2.

The portion of the ultrasound body196passing through the hemostasis tube222is fixedly attached to the hemostasis tube222by bonding the inner surface of the hemostasis tube to the outer surface of the ultrasound body216using an adhesive, such as a glue or epoxy resin. The bond between the ultrasound body216and hemostasis tube222causes the ultrasound body, and consequently the ultrasound element220, to rotate within the lumen of the guiding catheter5when the positioning gear224is rotated. The bonding also provides a hemostatic seal preventing irrigation fluid introduced into the lumen of guiding catheter5from leaking out of the handle2through the hemostasis tube222.

For a more detailed discussion of the relationship between the second adjusting knob10band the rotation of the ultrasound element196, reference is now made to FIGS.38-40. The second adjusting knob10bis positioned proximal to the first adjusting knob10aand distal to handle grip12, and is thereby constrained along the longitudinal axis of handle2. The second adjusting knob10bcontains an internal gear226disposed to engage with a reduction gear228contained within handle2. The reduction gear228is attached to the distal end of the drive shaft206that exits the gear assembly208and extends distally to the second adjustment knob10b. The distal end of the drive shaft206is supported within a notch230of the mounting shaft16to allow torque from the internal gear226to be transferred to the reduction gear228without detrimental bending that can occur in long cantilevered members. As the second adjustment knob10bis pivoted about the longitudinal axis of the handle2, the internal gear226engages the reduction gear228and causes the drive shaft206to rotate. The proximal end of the drive shaft206extends through the distal face of the gear assembly208and is fixedly attached to a drive gear232within the gear assembly208. The gear assembly208contains one or more ratio gears234disposed to transmit torque from the drive gear232to the positioning gear224such that the positioning gear rotates when the second adjusting knob10bis pivoted about the longitudinal axis of handle2.

In one embodiment, the ratio gears234are selected to provide a 1:1 gear ratio between rotation of the second adjustment knob10battached to internal gear226and rotation of the positioning gear224and the attached ultrasound catheter196. The number and type of ratio gears234may cause the ultrasound catheter196to rotate in the same direction as the second adjusting knob10bis pivoted. For example, when adjusting the second adjusting knob10bis pivoted in a counter-clockwise direction, the ratio gears234should cause ultrasound catheter196to rotate in a counter-clockwise direction by rotating positioning gear224in a counter-clockwise direction. And, when the second adjusting knob10bis pivoted in a clockwise direction, the ratio gears should cause the ultrasound catheter196to rotate in a clockwise direction by rotating the positioning gear224in a clockwise direction. Ensuring that both the ultrasound catheter196and knob10brotate in the same direction allows for more intuitive control of the ultrasound catheter196by the user.

A 1:1 ratio of rotational movement between the second adjusting knob10band the ultrasound catheter196allows the user to more easily visualize the orientation of the ultrasound element220when the catheter is positioned within a patient. When a 1:1 ratio is used, the facing of the ultrasound element220can be further indicated to the user through the use of a raised bump or other tactile feature on adjusting knob10baligned with the ultrasound element220such that the tactile feature is within the ultrasound plane emitted by the ultrasound element220. The tactile feature allows the user to ascertain the orientation of the ultrasound element220by the feel of the tactile feature when gripping the adjusting knob10b.

The gear assembly208has a rectangular portion236that is positioned within the slot34of mounting shaft16. The rectangular portion236engages the sides of slot34and thereby constrains the gear assembly208and prevents it from rotating relative to the mounting shaft16. The gear assembly208also has an arcuate portion238extending above slot34. The radius of the arcuate portion238being substantially the same as the radius of the mounting shaft16, and the arcuate portion238generally extending above slot34such that the outer arcuate surface240is flush with the outer surface of the mounting shaft16. By extending the arcuate portion238above slot34, the drive shaft206avoids contact with the guiding catheter5and pillow block210.

This embodiment is advantageous in that it allows the user to adjust the rotational facing of the ultrasound element220using the second adjusting knob with the same hand used to manipulate the distal end of the guiding catheter with the first adjusting knob. Thus, the need for a separate handle attached to the ultrasound catheter used to rotate the ultrasound catheter relative to the guiding catheter is eliminated.

In another embodiment, as depicted inFIGS. 41-43, the handle2having a single adjusting knob10and a through lumen, as previously discussed, can be used with a diagnostic ultrasound catheter196. In this embodiment, ultrasound catheter196further includes a handle242attached to the proximal end218of the of the flexible body216.

The flexible body216of the ultrasound catheter196is slideably disposed through the lumen of the guiding catheter5in a coaxial configuration. In one embodiment, both the ultrasound catheter196and the guiding catheter5and handle2are steerable and/or deflectable. In this embodiment, the ultrasound catheter196and the guiding catheter5include one or more steering wires or pull wires (not shown) within the flexible bodies216,4of the ultrasound catheter196and the guiding catheter5, respectively. The handle242of the ultrasound catheter196and the handle2of the guiding catheter5include actuators for steering and/or deflecting the catheters.

In another embodiment, the handles2,242are different in size and/or shape so that a practitioner can easily distinguish one from the other during a medical procedure. In a further embodiment, the handles2,242are tactilely unique, meaning they each have a different feel or texture relative to the other. For example, one handle may have a soft or spongy surface while the other handle has a hard or stiff surface. Alternatively, one handle may have a smooth surface compared to a rough or textured surface on the other handle. It is advantageous to provide a system in which the handles242,2on the ultrasound catheter196and the guiding catheter5are different in size, shape and/or tactility to permit a practitioner to easily and quickly identify and distinguish the handle for controlling the ultrasound catheter196versus the handle for controlling the guiding catheter5during a medical procedure. For example, the handle2may be an embodiment of the full sized handles previously discussed, while the handle242may simply be a knob that is grasped to rotate the ultrasound catheter inside the guiding catheter5.

Referring toFIGS. 41-43, the ultrasound catheter196is configured in a coaxial relationship with both the handle2of the guiding catheter5and the lumen of the guiding catheter5. The handle2on the guiding catheter5may be manipulated to steer and/or deflect the guiding catheter5to direct the distal end307of the ultrasound catheter to focus fan312on a targeted anatomy. The handle242on the ultrasound catheter196may also be manipulated to steer and/or deflect the ultrasound catheter196. The guiding catheter5provides a pathway for delivering the distal portion214of the ultrasound catheter196to the desired anatomical area. The guiding catheter5also advantageously constrains the ultrasound catheter196within the lumen of the guiding catheter so that the ultrasound element220can be properly oriented toward the targeted anatomy. More specifically, the distal portion214of the ultrasound catheter196is advanced distally until the distal portion214extends beyond the distal end14of the guiding catheter5. In one embodiment, the distal portion214of the ultrasound catheter196is advanced about 5 cm to about 15 cm beyond the distal end14of the guiding catheter5.

Alternatively, the ultrasound catheter196may be provided in a “pre-advanced” state, such that the distal portion214is provided already advanced outside the distal end14. This advantageously allows the shaft of the ultrasound catheter196to have a smaller outer diameter in its middle portion, than would otherwise be required for the distal portion214due to the ultrasound elements220. This in turn allows the guiding catheter5to have a smaller lumen and a smaller outer diameter in turn. An ultrasound catheter196in a pre-advanced state can be used with embodiments of handle2having a second adjusting knob10b, as described above, because the bond between the ultrasound catheter196and the hemostasis tube222prevents axial movement of the ultrasound catheter relative to the handle2.

The handle242of the ultrasound catheter196can be rotated relative to handle2causing the distal portion214of the ultrasound catheter196to also rotate axially within the lumen of the guiding catheter5. Thus, the guiding catheter5allows the user to steer the ultrasound catheter196to the desired site by deflecting the distal end14using the adjusting knob10, and also advantageously assists in properly orienting the ultrasound fan244of the ultrasound element220in relation to the tissue to be visualized.

The combination of the steering elements above is uniquely advantageous, in particular for orienting the ultrasound fan244toward targeted anatomy. In particular, in prior art actuators for ultrasound catheters, the operator may bend the distal end of the catheter in a direction to move the catheter into or close to the relevant anatomy, only to find that while the guiding catheter is in position, the ultrasound fan is not oriented toward the targeted anatomy. The operator must rotate or twist the entire catheter to orient the fan in the proper direction. Naturally, when a bent catheter is rotated, the bend causes it to move out of position entirely, as it is no longer oriented correctly. Due to the narrow nature of 2D ultrasound fans, the operator may find himself repeatedly bending and twisting in succession to find the proper orientation, requiring a great deal of skill and experience to accomplish the task in a reasonable amount of time. In some cases, the catheter simply cannot reach the desired position. In contrast, with the present invention, the guiding catheter5is actuated to provide the proper bend. If the fan244is not properly oriented, the operator simply grasps handle242and twists it, or in other embodiments, pivots the second adjusting knob10b. Because guiding catheter5does not rotate with the ultrasound catheter196, the bend is not moved, only the orientation of the fan is changed. Thus, the fan is quite easily oriented toward the targeted anatomy. The inventors have found that these two handles/actuators combine in a surprising way to allow easy and intuitive manipulation of the ultrasound fan244.

In an embodiment, the ultrasound element220of the ultrasound catheter196can include a linear phased array of ultrasound elements, e.g.,64elements. A lens246can cover the ultrasound elements, and may be rounded or flat. The lens246may be made of materials that transmit sound at a velocity matching the velocity of sound in blood. The ultrasound elements220are operatively coupled to an ultrasound system Referring toFIGS. 41 and 43, the ultrasound element220is mounted in a housing that is affixed to the distal end214of the ultrasound body216.

In another embodiment, the ultrasound catheter169may include an ultrasound element220such as a radiofrequency (RF) ultrasound element or a high intensity focused ultrasound element, also referred to as a HIFU ultrasound element, that, in some cases, may utilize a linear phased array transducer. An RF ultrasound element is a conductive metal having, in one embodiment, a concave surface as described above. The metal may be any conductive metal or a metal alloy consisting of one or more of gold, silver, platinum, iridium, titanium, tantalum, zirconium, vanadium, niobium, hafnium, aluminum, silicone, tin, chromium, molybdenum, tungsten, manganese, beryllium, cobalt, nickel, palladium, osmium, rhenium, technetium, rhodium, ruthenium, cadmium, zinc, germanium, antimony, bismuth, boron, scandium and metals of the lanthanide and actinide series, or any other biocompatible material. In some embodiments, it may be desirable to include a layer of biocompatible materials covering the conductive metal. In another embodiment, the ultrasound catheter196may incorporate other types of ultrasound elements suitable for forming ablation lesions such as a microwave transmitter, a cryogenic element, an optical element, or an acoustic transducer, for example a high intensity focused ultrasound transducer.

The ultrasound catheters described and depicted herein are directional. In other words, successful diagnostic imaging depends on proper orientation of the ultrasound element220relative to the target tissue.

In one embodiment, the guiding catheter5, the ultrasound catheter196, or both may include one or more electrodes248coupled to the flexible body4,216. Alternatively, the flexible bodies4,216can include a magnetic tracking coil (not shown). The electrode248or magnetic tracking coil may be used in conjunction with an electroanatomical mapping system to provide location information for the guiding catheter or ultrasound catheter. Suitable systems include the St Jude Medical Ensite™ Electroanatomical Modeling System, the Biosense Webster Carto™ System, a fluoroscopy system, a magnetic location system such as the gMPS system form Mediguide Ltd. Likewise, the flexible bodies4,216may include one or more radiopaque portions for tracking in a fluoroscopy system. As described above, such systems include the EnSite NavX™ System commercially available from St. Jude Medical, Inc. and as generally shown with reference to commonly assigned U.S. Pat. No. 7,263,397 entitled “Method and Apparatus for Catheter Navigation and location and Mapping in the Heart,” the disclosure of which is hereby incorporated by herein by reference in its entirety. Alternative systems include Biosense Webster Carto™ System, commonly available fluoroscopy systems or a magnetic location system such as the gMPS system from Mediguide Ltd., and as generally shown with reference to U.S. Pat. No. 7,386,339, entitled “Medical Imaging and Navigation System,” the disclosure of which is incorporated herein by reference in its entirety.

In a further embodiment, to assist in orienting and locating the distal end of the ultrasound catheter196, the ultrasound catheter196can include one or more electrodes250disposed on the distal portion214of the ultrasound body216(seeFIG. 39, for example). The electrodes250may advantageously be used to orient the ultrasound catheter196to ensure that the fan244emitted by the ultrasound element220is facing or oriented towards the target anatomy. In a particular configuration, the electrodes250may be unipolar or bipolar electrogram (EGM) electrodes adapted to measure electrical activity present on a surface of the tissue. For example, in one embodiment, a pair of bipolar electrodes250is disposed on an outer surface of the distal end214, the electrodes in the pair being disposed on opposite sides of the ultrasound element220. In another embodiment, two pairs of bipolar electrodes250are used. The electrodes250are disposed on opposite sides of the ultrasound element220in a lateral direction generally perpendicular to a central axis of the elongate body of the ultrasound catheter196. Alternatively, or in addition to the foregoing, a bipolar pair of electrodes250may be disposed on opposite sides of the ultrasound element220in a lateral direction generally parallel to a central axis of the catheter body. In one embodiment, a side portion of the electrodes250is covered in a biocompatible material to prevent pacing and/or sensing of tissue that may contact the side portion of the electrodes250.

The electrodes250can be coupled to an EGM-measurement circuit and a display or user interface for displaying EGM data. The electrodes250can be used for diagnostic purposes, for example, to confirm that an effective lesion has been created. In this embodiment, the electrodes250are coupled to an impedance-measuring circuit. An ablation lesion is non-conductive scar tissue; thus, the lesion blocks electrical signals. Because impedance measures resistance, the effectiveness of an ablation lesion can be determined based on impedance measurements. Impedance can be measured before, during or after applying ablative energy to the tissue. If an effective lesion has been created, the impedance will be higher after ablation compared to pre-ablation impedance measurements, as generally shown in commonly assigned U.S. patent application Ser. No. 12/622,488, entitled “System and method for assessing lesions in tissue,” the disclosure of which is hereby incorporated by reference in its entirety. Likewise, the electrodes250can be used to determine the proximity of the catheter to tissue, as generally shown in commonly assigned U.S. patent application Ser. No. 12/650,060, entitled “System and method for assessing coupling between an electrode and tissue,” the disclosure of which is hereby incorporated by reference in its entirety.

In another embodiment, the ultrasound catheter196includes one or more temperature sensors (not shown), such as thermistors or thermocouples, disposed on the distal portion307of the ultrasound body216. The one or more temperature sensors are positioned to measure the temperature of the ultrasound element220, and/or the tissue. In one embodiment, temperature sensors are positioned distally and/or proximally of the ultrasound element220. Temperature readings from the one or more temperature sensors may be output and presented as advisory data to a user (analogous to the above relating to the state of the electrode(s)). For example, temperature readings may be presented via a display (e.g., a color, number, or symbol), a tone (e.g., an audible alarm), and/or haptic or vibratory feedback. In addition, the temperature data may be used to assist in lesion assessment.

In another embodiment, as depicted inFIGS. 44 and 45, the diameter of the guiding catheter5can be reduced when the pull wires38a,38bare flat wires252having a generally rectangular cross section taken orthogonally to the longitudinal axis of the flat wire252. The flat wire252is preferably composed of stainless steel, although alternative materials used for conventional round pull wires are also suitable. The flat wires252preferably has dimensions of about 0.002 inches by about 0.006 inches, and more preferably about 0.004 inches by 0.012 inches. Flat wires252allow the outer diameter of guiding catheter5to be reduced which is beneficial in that it allows the sheath to be used in smaller body lumens. An exemplary guiding catheter containing flat wires is described in U.S. patent application Ser. No. 11/647,313 entitled “Steerable Catheter Using Flat Pull Wires and Method of Making Same,” the disclosure of which is incorporated herein by reference in its entirety.

In yet another embodiment, guiding catheter5can include a braided wire assembly254to strengthen the guiding catheter5. The braided wire assembly254can be formed of stainless steel wire, including for example 0.003 inch high tensile stainless steel wire. Braided wire assembly254can be formed in a standard braid pattern and density, for example, about 16 wires at about 45 to about 60 picks per inch (“PPI”) density. Alternatively, a braid may be used that is characterized by a varying braid density. For example, braided wire assembly254can be characterized by a first braid density at the proximal end of catheter5and then transition to one or more different braid densities as braided wire assembly254approaches the distal end14of the guiding catheter5. The braid density of distal end14can be greater or less than the braid density at the retaining nut36. In one example, the braid density at the retaining nut36is about 50 PPI and the braid density at the distal end14is about 10 PPI. In other embodiments, the braid density at the distal end14is about 20% to about 35% of the braid density at the retaining nut36.

The braided wire assembly254can be designed to have transitional braid densities starting at one braid density and transitioning to a lower braid density. In one embodiment, the braid may begin at a braid density of about 50 to 60 PPI, and more preferably between about 50 and about 55 PPI, and then transition to a braid density at the distal end14of about 5 to about 15 PPI. The braid density may transition slowly, or it may change using one or more segments. For example, there can be an intermediate zone with a braid density of about 30 to 45 PPI. Variations in the braid density of the braided wire assembly254can be used to increase or decrease the flexibility of the guiding catheter5and to decrease the overall diameter of the guiding catheter5in sections having a decreased braid density. An exemplary guiding catheter containing a braided wire assembly is described in U.S. patent application Ser. No. 11/647,313 entitled “Steerable Catheter Using Flat Pull Wires and Method of Making Same,” the disclosure of which is incorporated herein by reference in its entirety.

As can be understood fromFIG. 46, which is a diagrammatic illustration of the control handle2of the subject invention being employed in a surgical procedure on a patient300, the distal end14of the guiding catheter body4is inserted into the patient300(e.g., intravenously via a body lumen302of the patient300, percutaneously, or via other avenues for entering the patient's body). The distal end14of the catheter body4is advanced until positioned in a selected location within the patient300(e.g., within a chamber304of the patient's heart306or other organ, with a body cavity of the patient, etc.). The distal end14of the catheter body4is then deflected by rotating adjustment knob10,10aabout the longitudinal axis of the handle2. As can be understood fromFIGS. 1-44, this causes the slides30,32within the handle2to displace along the longitudinal axis in opposite directions. Since each slide30,32is coupled to its respective deflection wire38and each deflection wire runs through the guiding catheter body4and is coupled to the distal end14, the distal end14of the catheter body4is deflected. The orientation of the ultrasound fan244can then be adjusted by rotating the ultrasound catheter196relative to the guiding catheter5. The ultrasound adjustment can be accomplished in one embodiment by rotating adjusting knob10babout the longitudinal axis of handle2to, in a preferred embodiment, a 1:1 angular rotation of the ultrasound fan about the longitudinal axis of the distal end14of the guiding catheter5. In another embodiment, the ultrasound adjustment can be accomplished by rotating handle242relative to handle2causing the ultrasound catheter196to rotate within the lumen of the guiding catheter5. In both embodiments, the adjustment of the ultrasound fan244orientation can be accomplished without changing the deflection of the distal end14of the guiding catheter5.

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.