US-12622716-B2 - Systems, devices and methods for generating patterns of voltage pulses and electrical arcs between spaced-apart electrode pairs in intravascular lithotripsy

US12622716B2US 12622716 B2US12622716 B2US 12622716B2US-12622716-B2

Abstract

Various embodiments of the systems, methods and devices are provided for breaking up calcified lesions in an anatomical conduit. More specifically, an electrical arc is generated between two spaced-apart electrodes disposed within a fluid-filled balloon, creating a subsonic pressure wave. In some embodiments, the electrodes comprise a plurality of points that allow the electrical arc to form at any one of the plurality of points to, among other things, extend the electrode life.

Inventors

J. Samuel Batchelder
John R. Ballard
Robert D'Agostino
Michael P. Brenzel
Jason W. Staab

Assignees

CARDIOVASCULAR SYSTEMS, INC.

Dates

Publication Date: 20260512
Application Date: 20211004

Claims (12)

1 . A lithoplasty system for generating voltage pulses, comprising: an elongate member; a fluid inflatable balloon surrounding a portion of the elongate member; a fluid reservoir in fluid communication with an interior of the fluid inflatable balloon; a plurality of pairs of spaced-apart electrodes disposed within the interior of the fluid inflatable balloon, wherein each pair of spaced-apart electrodes is spaced axially away from an adjacent pair of spaced-apart electrodes; a voltage pulse generator configured to generate voltage pulses and in operative electrical communication with each pair of the plurality of spaced-apart electrodes; and a controller in operative communication with the voltage pulse generator and configured to control generation of the voltage pulses, the controller comprising a processor in operative communication with a memory and configured to execute programmed instructions, wherein the programmed instructions control the voltage pulse generator to cause generated voltage pulses to comprise a pattern of voltage pulses, which cause adjacent pressure waves to be generated by adjacent pairs of spaced-apart electrodes in a fashion whereby adjacent pressure wave interfere with each other resulting in a central node caused by and between the adjacent pressure waves, wherein the pattern of voltage pulses is applied to the plurality of pairs of spaced-apart electrodes, wherein the pattern of voltage pulses cause adjacent pressure waves to be generated by adjacent pairs of spaced-apart electrodes with a predetermined delay between the adjacent pressure waves, and wherein the central node caused by and between the adjacent pressure waves is proximally or distally shifted along an axial length of the fluid inflatable balloon as compared to when there is no delay between the adjacent pressure waves.
2 . The lithoplasty system of claim 1 , further comprising the programmed instructions configured to initiate the pattern of voltage pulses, wherein the pattern comprises a plurality of voltage pulses, and wherein each one of the plurality of voltage pulses is applied to the plurality of pairs of spaced-apart electrodes in a pattern comprising axial translation of the applied voltage pulses to the plurality of pairs of spaced-apart electrodes.
3 . The lithoplasty system of claim 2 , wherein the pattern comprises axial translation of the applied voltage pulses to each one of the plurality of pairs of spaced-apart electrodes moving in a proximal to a distal direction.
4 . The lithoplasty system of claim 2 , wherein the pattern comprises axial translation of the applied voltage pulses to each one of the plurality of pairs of spaced-apart electrodes moving in a distal to a proximal direction.
5 . The lithoplasty system of claim 2 , wherein each one of the applied voltage pulses in the pattern of voltage pulses is configured to generate an electrical arc between at least one of the plurality of pairs of spaced-apart electrodes.
6 . The lithoplasty system of claim 5 , wherein the generated electrical arcs comprise a pattern that is responsive to the pattern of voltage pulses.
7 . The lithoplasty system of claim 5 , wherein the generated electric arcs comprise a pattern that includes axial translation of the generated electrical arcs within the fluid inflatable balloon.
8 . The lithoplasty system of claim 5 , wherein the generated electrical arcs comprise a pattern that includes a predetermined delay time between voltage pulses.
9 . The lithoplasty system of claim 8 , wherein the generated electric arcs further comprise a pattern that includes axial translation of the generated electrical arcs through the fluid inflatable balloon.
10 . The lithoplasty system of claim 1 , wherein the pattern of voltage pulses further comprises applying the plurality of voltage pulses to the plurality of pairs of spaced-apart electrodes in an axially translating pattern.
11 . A lithoplasty system for generating voltage pulses and electrical arcs, comprising: an elongate member; a fluid inflatable balloon surrounding a portion of the elongate member; a fluid reservoir in fluid communication with an interior of the fluid inflatable balloon; a plurality of pairs of spaced-apart electrodes disposed within the interior of the fluid inflatable balloon, wherein each pair of spaced-apart electrodes is spaced axially away from an adjacent pair of spaced-apart electrodes, at least some of the pairs of spaced apart electrodes comprising two or more radially spaced-apart spark gaps; a voltage pulse generator configured to generate voltage pulses and in operative electrical communication with each pair of the plurality of spaced-apart electrodes; and a controller in operative communication with the voltage pulse generator and configured to control generation of the voltage pulses to create a pattern of voltage pulses, the controller comprising a processor in operative communication with a memory and configured to execute programmed instructions, wherein the pattern of voltage pulses is applied to the plurality of pairs of spaced-apart electrodes, wherein the programmed instructions are further configured to apply at least some of the generated voltage pulses to the plurality of pairs of spaced-apart electrodes in an axially translating pattern, wherein each one of the applied voltage pulses is configured to generate an electrical arc between one pair of spaced-electrodes in the plurality of pairs of spaced-apart electrodes, wherein the generated electrical arcs are further responsive to the pattern of voltage pulses, wherein the pattern of voltage pulses cause adjacent pressure waves to be generated by adjacent pairs of spaced-apart electrodes, in a fashion whereby adjacent pressure wave interfere with each other resulting in a central node caused by and between the adjacent pressure waves, wherein at least some of the generated electrical arcs are configured to occur across the radially spaced-apart spark gaps, wherein at least some of the generated electrical arcs are configured to be generated in an axially translating pattern within the fluid inflatable balloon in accordance with the programmed instructions, wherein the pattern of voltage pulses cause adjacent pressure waves to be generated by adjacent pairs of spaced-apart electrodes with a predetermined delay between the adjacent pressure waves, and wherein the central node caused by and between the adjacent pressure waves is proximally or distally shifted along an axial length of the fluid inflatable balloon as compared to when there is no delay between the adjacent pressure waves.
12 . The lithoplasty system of claim 11 , wherein at least some of the generated electrical arcs comprise a radial location that is different than a radial location of at least some of the remaining electrical arcs.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application Ser. No. 63/229737, filed Aug. 5, 2021, entitled SYSTEMS, DEVICES AND METHODS FOR GENERATING SUBSONIC PRESSURE WAVES IN INTRAVASCULAR LITHOTRIPSY, the entire contents of which are incorporated herein by reference. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT None BACKGROUND OF THE INVENTION Field of the Invention The invention relates to systems, devices and methods for breaking up calcified lesions in an anatomical conduit. More specifically, an electrical arc is generated between two electrodes disposed within a fluid-filled balloon, creating a subsonic pressure wave. Description of the Related Art A variety of techniques and instruments have been developed for use in the removal or repair of tissue in arteries and similar body passageways, including removal and/or cracking of calcified lesions within the passageway and/or formed within the wall defining the passageway. A frequent objective of such techniques and instruments is the removal of atherosclerotic plaque in a patient's arteries. Atherosclerosis is characterized by the buildup of fatty deposits (atheromas) in the intimal layer (i.e., under the endothelium) of a patient's blood vessels. Very often over time what initially is deposited as relatively soft, cholesterol-rich atheromatous material hardens into a calcified atherosclerotic plaque, often within the vessel wall. Such atheromas restrict the flow of blood, cause the vessel to be less compliant than normal, and therefore often are referred to as stenotic lesions or stenoses, the blocking material being referred to as stenotic material. If left untreated, such stenoses can cause angina, hypertension, myocardial infarction, strokes and the like. Angioplasty, or balloon angioplasty, is an endovascular procedure to treat by widening narrowed or obstructed arteries or veins, typically to treat arterial atherosclerosis. A collapsed balloon is typically passed through a pre-positioned catheter and over a guide wire into the narrowed occlusion and then inflated to a fixed size. The balloon forces expansion of the occlusion within the vessel and the surrounding muscular wall until the occlusion yields from the radial force applied by the expanding balloon, opening up the blood vessel with a lumen inner diameter that is similar to the native vessel in the occlusion area and, thereby, improving blood flow. The angioplasty procedure presents some risks and complications, including but not limited to: arterial rupture or other damage to the vessel wall tissue from over-inflation of the balloon catheter, the use of an inappropriately large or stiff balloon, the presence of a calcified target vessel; and/or hematoma or pseudoaneurysm formation at the access site. Generally, the pressures produced by traditional balloon angioplasty systems is in the range of 10-15 atm, but pressures may at times be higher. As described above, the primary problem with known angioplasty systems and methods is that the occlusion yields over a relatively short time period at high stress and strain rate, often resulting in damage or dissection of the conduit, e.g., blood vessel, wall tissue. Shockwave Medical, Inc., markets an alternative to traditional relatively high pressure balloon angioplasty. The Shockwave Medical, Inc., intravascular lithotripsy system generates “shock waves” within a fluid-filled balloon. Shockwave Medical claims that generated “shock waves” travel at supersonic speed through the balloon fluid, through the balloon material to interact with the vessel wall tissue, stenosis and/or calcification. The Shockwave Medical Inc., system requires a relatively close spacing between electrodes in an electrode pair wherein the spark gap is disposed. Shockwave Medical's currently known systems provides relatively small axial coverage of lesions. The structure of Shockwave Medical's electrode pairs thus requires additional electrode pairs spaced apart axially from each other and/or a translatable, slidable electrode pair carrier that may be used to translate the electrode pair(s) to better cover an elongated lesion. Various embodiments of the present invention address these issues, among others, discussed above. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS These drawings are exemplary illustrations of certain embodiments and, as such, are not intended to limit the disclosure. FIGURE l illustrates a perspective and partial cutaway view of a distal region of one embodiment of the present invention. FIG. 2 illustrates a perspective view of a distal region of one embodiment of the present invention. FIG. 3 illustrates a perspective view of a distal region of one embodiment of the present invention. FIG. 4 illustrates a side, cutaway view of a distal region of one embodiment of the present invention. FIG. 5 illustrates a perspective, cutaway view of a portion of a distal region of one