Lesion crossing shock wave catheter
The present invention provides a catheter for treating occlusions in body lumens. The catheter includes a catheter body that is fillable with fluid. An impactor is connected to the distal end of the catheter body and has a proximal end inside the catheter body and a distal end outside the catheter body. The catheter also includes a shock wave source configured to generate a shock wave, and a deflector coupled to the proximal end of the impactor in between the shock wave source and distal end of the catheter body. When the shock wave source generates a shock wave, the shock wave impinges on the deflector causing the deflector to advance in a forward direction in conjunction with the impactor such that the distal end of the impactor delivers a mechanical force to the occlusion to restore flow to the body lumen.
1 . A catheter for treating an occlusion in a body lumen, the catheter comprising:
a catheter body having a distal end, the catheter body being fillable with a fluid;
an impactor connected to the distal end of the catheter body, the impactor having a proximal end inside the catheter body and a distal end outside the catheter body;
a shock wave source comprising an electrode pair configured to generate a shock wave; and
a deflector coupled to the proximal end of the impactor in between the shock wave source and the distal end of the catheter body, wherein, when the shock wave source generates a shock wave, the shock wave impinges on the deflector causing the deflector to advance relative to the catheter body in a distal direction in conjunction with the impactor such that the distal end of the impactor delivers a mechanical force to the occlusion.
2 . The catheter of claim 1 , wherein the distal end of the catheter body comprises a flexible material that causes the impactor to move proximally relative to the catheter body after the shock wave has terminated.
3 . The catheter of claim 1 , wherein, when the shock wave source generates a shock wave, the deflector is configured to advance distally between 50 μm and 100 μm.
4 . The catheter of claim 1 , wherein, when the shock wave source generates a shock wave, the deflector deflects a portion of shock wave energy in a direction transverse to the catheter.
5 . The catheter of claim 1 , wherein the catheter body has a longitudinal axis, and the deflector includes a proximal surface that faces the shock wave source, and
a deflector angle is defined between the proximal surface of the deflector and the longitudinal axis of the catheter body, the deflector angle being between 120° and 150°.
6 . The catheter of claim 1 , further comprising:
a cylinder mounted within the catheter body; and
a shaft mounted to a proximal end of the deflector, wherein the shaft is configured to slide within the cylinder.
7 . The catheter of claim 6 , further comprising a spacer that projects outward between the shaft and the cylinder to retain the shaft at a center of the cylinder.
8 . The catheter of claim 1 , wherein the impactor includes a laser-cut metal tube.
9 . The catheter of claim 1 , wherein the impactor includes a guide wire lumen sized to receive a guide wire.
10 . The catheter of claim 1 , further comprising a tapered distal tip coupled to the distal end of the catheter body, wherein the tapered distal tip is configured to advance in the distal direction in conjunction with the deflector and the impactor to deliver the mechanical force to the occlusion.
11 . The catheter of claim 10 , wherein the tapered distal tip comprises a rigid material.
12 . The catheter of claim 1 , wherein the catheter body comprises a plurality of folds disposed on the catheter body, the plurality of folds configured to expand to an unfolded position in response to generation of a shock wave and to return to a folded position after the shock wave has terminated.
13 . The catheter of claim 12 , wherein the catheter body comprises a vibrating section in between the folds and the distal end of the catheter body and a stationary section located on a proximal end of the catheter body that terminates at the folds; and wherein the vibrating section is configured to move in the distal direction as the folds expand to the unfolded position and to move proximally relative to the catheter body when the folds return to the folded position.
14 . The catheter of claim 1 , wherein the shock wave source comprises
a cylindrical inner conductive sheath mounted within the catheter, the cylindrical inner conductive sheath having a distal side edge;
a cylindrical outer conductive sheath mounted circumferentially around the cylindrical inner conductive sheath within the catheter, the cylindrical outer conductive sheath having a distal side edge proximal to the distal side edge of the cylindrical inner conductive sheath; and
an insulation sheath mounted within the catheter between the cylindrical outer conductive sheath and the cylindrical inner conductive sheath;
wherein, when voltage pulses are applied across the cylindrical inner conductive sheath and the cylindrical outer conductive sheath, current flows across an arcing region between the cylindrical inner conductive sheath and the cylindrical outer conductive sheath to generate shock waves.
15 . The catheter of claim 1 , wherein the shock wave source comprises:
a cylindrical conductive sheath mounted within the catheter, the cylindrical conductive sheath having a distal side edge;
an insulation sheath mounted circumferentially within the cylindrical conductive sheath, the insulation sheath having a distal side edge proximal to the distal side edge of the cylindrical conductive sheath;
a flat coil disposed on an inner surface of the insulation sheath and the distal side edge of the insulation sheath; and
wherein when voltage pulses are applied across the flat coil and the cylindrical conductive sheath, current flows across an arcing region between the flat coil and the cylindrical conductive sheath to generate shock waves.
16 . A catheter for treating an occlusion in a body lumen, the catheter comprising:
a catheter body having a distal end, the catheter body being fillable with a fluid;
an impactor connected to the distal end of the catheter body, the impactor having a proximal end inside the catheter body and a distal end outside the catheter body;
a shock wave source comprising at least one optical fiber configured to generate a shock wave; and
a deflector coupled to the proximal end of the impactor in between the shock wave source and the distal end of the catheter body, wherein, when the shock wave source generates a shock wave, the shock wave impinges on the deflector causing the deflector to advance relative to the catheter body in a distal direction in conjunction with the impactor such that the distal end of the impactor delivers a mechanical force to the occlusion.
17 . The catheter of claim 16 , wherein the distal end of the catheter body comprises a flexible material that causes the impactor to move proximally relative to the catheter body after the shock wave has terminated.
18 . The catheter of claim 16 , wherein, when the shock wave source generates the shock wave, the deflector is configured to advance distally between 50 μm and 100 μm.
19 . The catheter of claim 16 , wherein, when the shock wave source generates the shock wave, the deflector deflects a portion of shock wave energy in a direction transverse to the catheter.
20 . The catheter of claim 16 , wherein the catheter body has a longitudinal axis, and the deflector includes a proximal surface that faces the shock wave source, and
a deflector angle is defined between the proximal surface of the deflector and the longitudinal axis of the catheter body, the deflector angle being between 120° and 150°.
21 . The catheter of claim 16 , further comprising:
a cylinder mounted within the catheter body; and
a shaft mounted to a proximal end of the deflector, wherein the shaft is configured to slide within the cylinder.
22 . The catheter of claim 21 , further comprising a spacer that projects outward between the shaft and the cylinder to retain the shaft at a center of the cylinder.
23 . The catheter of claim 16 , wherein the shock wave source is optically coupled to a laser that generates pulses of light, said pulses of light being emitted from the at least one optical fiber.
24 . The catheter of claim 16 , wherein the impactor includes a laser-cut metal tube.
25 . The catheter of claim 16 , wherein the impactor includes a guide wire lumen sized to receive a guide wire.
26 . The catheter of claim 16 , further comprising a tapered distal tip coupled to the distal end of the catheter body, wherein the tapered distal tip is configured to advance in the distal direction in conjunction with the deflector and the impactor to deliver the mechanical force to the occlusion.
27 . The catheter of claim 26 , wherein the tapered distal tip comprises a rigid material.
28 . The catheter of claim 16 , wherein the catheter body comprises a plurality of folds disposed on the catheter body, the plurality of folds configured to expand to an unfolded position in response to generation of the shock wave and to return to a folded position after the shock wave has terminated.
29 . The catheter of claim 28 , wherein the catheter body comprises a vibrating section in between the folds and the distal end of the catheter body and a stationary section located on a proximal end of the catheter body that terminates at the folds; and wherein the vibrating section is configured to move in the distal direction as the folds expand to the unfolded position and to move proximally relative to the catheter body when the folds return to the folded position.
30 . A method of treating an occlusion in a body lumen, comprising:
positioning an impactor adjacent to the occlusion in the body lumen, and
energizing a shock wave source to generate a shock wave within a catheter body filled with a fluid,
wherein the shock wave impinges on a deflector coupled to the impactor within the catheter body to advance the impactor in a first direction to deliver a mechanical force to the occlusion.
31 . The method of claim 30 , further comprising:
stretching a flexible material of the catheter body as the impactor is advanced,
wherein the flexible material causes the impactor to move in a second direction opposite the first direction after the shock wave is terminated.
32 . The method of claim 30 , further comprising advancing a guide wire through the catheter body and the impactor to aid in insertion and removal of the catheter body.