Control, method, and apparatus for IVL systems

Abstract

Various embodiments of systems, methods, and apparatus are provided for the controlled operation of intravascular lubrication (IVL) for disrupting calcified lesions within anatomical conduits. More specifically, control configurations are disclosed relating to managing and / or supplying electrical energy to generate an electric arc between a pair of spaced electrodes arranged within a fluid-filled balloon, and generating a stable, constant, or slightly increasing pressure output over at least 300 voltage pulses. The disclosed control configurations further determine whether the electric arc has been successfully generated.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority from Provisional Application No. 63 / 650,872 filed on May 22, 2024, entitled "CONTROL OF IVL SYSTEMS, METHODS AND DEVICES", Provisional Application No. 63 / 580,547 filed on September 5, 2023, entitled "DEVICES, SYSTEMS, AND METHODS OF INTRAVASCULAR LITHOTRIPSY", PCT Application No. PCT / US2023 / 79209 filed on November 9, 2023, entitled "CONTROL OF IVL SYSTEMS, DEVICES AND METHODS AND DEVICES", U.S. Utility Application No. 18 / 506,305 filed on November 10, 2023, entitled "CONTROL OF IVL SYSTEMS, DEVICES AND METHODS THEREOF", and PCT / US2023 / 085868 filed on December 23, 2023, entitled "INTRAVASCULAR LITHOTRIPSY SYSTEM WITH IMPROVED DURABILITY, EFFICIENCY AND PRESSURE OUTPUT VARIABILITY", the entire contents of each of which are incorporated herein by reference.

[0002] STATEMENT OF FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT None

[0003] The present disclosure relates to devices, systems, and methods for breaking calcified lesions within an anatomical duct. More specifically, the present disclosure relates to devices, systems, and methods for applying an electric arc between spaced electrodes disposed in a fluid-filled member to generate flow and pressure waves.

Background Art

[0004] Various techniques and devices have been developed for use in the removal or repair of tissues in arteries and similar internal pathways, including the removal and / or fragmentation of calcified lesions formed within and / or within the walls defining the pathways. The general purpose of such techniques and devices is to remove atherosclerotic plaques in a patient's arteries. Atherosclerosis is characterized by the accumulation of fatty deposits (atheroma) in the intima layer (i.e., beneath the endothelium) of a patient's blood vessels. Often, over time, what initially accumulates as relatively soft, cholesterol-rich atheroma material hardens and calcifies into atherosclerotic plaques, often forming within the blood vessel walls. Such atheromas restrict blood flow and reduce the flexibility of the blood vessels compared to normal ones, and are therefore often called stenotic lesions or stenosis, with the obstructing material being called stenotic material. If left untreated, such stenosis can lead to angina pectoris, hypertension, myocardial infarction, seizures, etc.

[0005] Angioplasty, or balloon angioplasty, is an endovascular procedure that treats narrowed or blocked arteries or veins by widening them, typically in the treatment of atherosclerosis. Typically, a folded balloon is inserted through a pre-positioned catheter, guided along a guidewire into the narrowed or blocked area, and then inflated to a fixed pressure. The balloon expands the blocked area within the vessel and the surrounding muscle wall until the radial force applied by the balloon causes it to flex, widening the vessel to approximately the same lumen diameter as the original vessel in the blocked area, thereby improving blood flow.

[0006] Angioplasty procedures carry several risks and complications, including, but are not limited to, arterial rupture or other damage to the vascular wall tissue due to excessive inflation of the balloon catheter, the use of an inappropriately large or rigid balloon, the presence of calcified target vessels, and / or the formation of hematomas or pseudoaneurysms at the access site. Generally, the pressure generated by conventional balloon angioplasty systems ranges from 10 to 15 atmospheres, although pressures can be higher. As mentioned above, the main problem with known angioplasty systems and methods is that the occlusion collapses within a relatively short period of time with high stress and strain rates, often resulting in damage or dissection of the conduit, such as blood vessels or wall tissues. [Overview of the Initiative]

[0007] Conventional systems may employ coarse system control. For example, cutting off the power supply from the power source may be used as the primary means of adjusting the amount of energy applied to the treatment site. Such a technique is taught in U.S. Patent No. 8,728,091, in which the current is monitored while a voltage is applied by a pulse generator. When the current exceeds a predetermined threshold, the voltage is cut off by the pulse generator. As described in further detail herein, improved techniques for power characteristic control can support more effective and consistent treatment. For example, improved endurance, higher frequencies, and substantially equivalent pressure output across a greater number of voltage pulses than previously possible can be achieved using embodiments of this disclosure.

[0008] Various embodiments of this disclosure can address, in particular, the problems described above.

[0009] The following drawings are illustrative illustrations of specific embodiments and are not intended to limit this disclosure. [Brief explanation of the drawing]

[0010] [Figure 1]This is a diagram illustrating a schematic intravascular lithotripsy (IVL) mechanism according to one or more embodiments of the present disclosure. [Figure 2] This is a flowchart for controlling and supplying voltage to electrodes, and for generating pressure waves, according to one or more embodiments of the present disclosure. [Figure 3A] Figures 1 and 2 show some of the circuit configurations of one or more IVL mechanisms and control operations according to one or more embodiments of the present disclosure. [Figure 3B] Figures 1 and 2 show some of the circuit configurations of one or more IVL mechanisms and control operations according to one or more embodiments of the present disclosure. [Figure 4A] This is a partial diagram of one or more additional circuit configurations of the IVL mechanism and control operation shown in Figures 1 and 2, according to one or more embodiments of the present disclosure. [Figure 4B] This is a partial diagram of one or more additional circuit configurations of the IVL mechanism and control operation shown in Figures 1 and 2, according to one or more embodiments of the present disclosure. [Figure 4C] This is a partial diagram of one or more additional circuit configurations of the IVL mechanism and control operation shown in Figures 1 and 2, according to one or more embodiments of the present disclosure. [Figure 4D] This is a partial diagram of one or more additional circuit configurations of the IVL mechanism and control operation shown in Figures 1 and 2, according to one or more embodiments of the present disclosure. [Figure 5] This is a flowchart for controlling the delivery of voltage to electrodes and the generation of shock waves according to one or more embodiments of the present disclosure. [Figure 6] This is a flow of control operations according to one or more embodiments of the present disclosure. [Figure 7] This is a schematic comparison of the voltages applied to known IVL devices and embodiments of the IVL device according to this disclosure. [Figure 8]This figure shows a schematic comparison of the average peak pressure generated over 80 voltage pulses by known IVL devices and embodiments of the IVL device according to this disclosure. [Figure 9] This figure provides a schematic comparison of the average peak pressures generated over 80 voltage pulses by known IVL devices and over a predetermined maximum number of voltage pulses by embodiments of the IVL devices according to this disclosure. [Figure 10] This is a diagram illustrating the exemplary flowchart method according to this disclosure. [Figure 11] This is an illustrative flowchart provided in this disclosure. [Modes for carrying out the invention]

[0011] Conventional endovascular lithotripsy (IVL) devices, systems, and methods can generate a spark (arc) between discharge electrodes by applying high-energy power. Under appropriate conditions, the spark generated by the immersed electrodes can create a pressure wave in the medium, which can be applied to treat (destroy) calcified lesions in the patient's vascular system. It is recognized that proper control of such high-energy systems can be crucial for providing effective and safe treatment.

[0012] Referring to Figure 1, a schematic arrangement of several parts of an exemplary IVL system 12 is shown, illustrating the control elements in this disclosure. The exemplary IVL system 12 comprises a catheter assembly 14 having a long body realized as a catheter with a guidewire 15 and a fluid-fillable member, the fluid-fillable member being, for example, an exemplary inflatable balloon 16, positioned near one end of the body and configured to inflate to receive fluid to facilitate IVL treatment. A pair of spaced electrodes 18 are shown positioned inside the balloon 16, at least some of the electrodes 18 being spaced apart from each other by a gap 17, generating an electric arc across the gap 17 between the spaced electrodes 18.

[0013] The spaced electrodes 18 are arranged in communication with an electrical pulse generation system 20 (as indicated by the dashed conductor) to receive high-voltage electrical energy for spark generation and generate a pressure wave for IVL treatment. In exemplary embodiments, one electrode may be grounded and the other supplied with high voltage from the electrical pulse generation system 20, but in some embodiments, any voltage difference may be applied. The electrical pulse generation system 20 includes an IVL control system 22, which may include a processor 24 that executes instructions stored in memory 26 and communication signals via circuit configuration 28 for IVL operation under the control of the processor. The processor 24, memory 26, and circuit 28 are arranged in communication with each other (as indicated by the dashed lines) to facilitate the disclosed operation.

[0014] Proper control of such high-energy systems may also require achieving sufficient energy at spaced electrodes. Given the high-energy environment and the micro-scale timescale of electron discharge, desirable energy control in such IVL devices and systems can be challenging. Furthermore, adaptable control methods may benefit the effectiveness of IVL. Adjustable energy delivery can increase efficient power delivery, which may reduce the risk to the patient. For example, it may be attempted to start from a predetermined starting voltage threshold and define a predetermined upper voltage threshold to form an acceptable voltage window. The acceptable voltage window may be coupled to one or more sequences of two or more generated voltage pulses having a magnitude that is confirmed to be within the acceptable voltage window. For example, if the magnitude of the sequence of generated voltage pulses falls below a predetermined upper voltage threshold, the target voltage may be increased by a predetermined amount, and another sequence of generated voltage pulses is performed. In other embodiments, the duration of voltage application may be changed, e.g., increased, by a predetermined amount, either alone or in combination with the increase in the target voltage.

[0015] Various embodiments may comprise the IVL control systems and methods described in PCT Application No. PCT / US2023 / 79209, filed November 9, 2023, entitled "CONTROL OF IVL SYSTEMS, DEVICES AND METHODS AND DEVICES", U.S. Utility Patent Application No. 18 / 506,305, filed November 10, 2023, entitled "CONTROL OF IVL SYSTEMS, DEVICES AND METHODS THEREOF", and PCT Application No. PCT / US2023 / 085868, filed December 23, 2023, entitled "INTRAVASCULAR LITHOTRIPSY SYSTEM WITH IMPROVED DURABILITY, EFFICIENCY AND PRESSURE OUTPUT VARIABILITY", the entire contents of each of which are incorporated herein by reference.

[0016] Referring now to Figure 2, there is shown an exemplary flow diagram of control 100 in the operation of an IVL system, specifically relating to the number of voltage pulses generated and the magnitude of the generated pulses. Such control operations may be governed by the electrical pulse generation system 20, and illustratively, by the IVL control system 22 described above in connection with Figure 1.

[0017] Referring now to Figure 2, there is shown a flow diagram of one embodiment of control 38 during operation of an IVL system described with respect to blocks 40-60. Such control operations may be governed by the electrical pulse generation system 20, and illustratively, by the IVL control system 22. As described in further detail herein, control 38 applies incremental changes to power parameters during repeated application of voltage, while monitoring parameters associated with spark generation. For example, progressively increasing the magnitude of voltage applied to the discharge electrode and / or the duration of voltage application can increase the likelihood of generating an effective spark without using excessive energy.

[0018] Furthermore, when sufficient sparks cannot be generated by increasing the duration of voltage applied to the discharge electrode, the gradual increase in voltage can further increase the possibility of generating effective sparks without using excessive power. Further, when sufficient sparks cannot be generated with the gradually increased voltage, the duration can be gradually increased again before the voltage is further increased. Therefore, it can be recognized that by performing controlled gradual increase in duration and voltage, effective spark generation and thus pressure wave generation can be achieved at or near the lowest required power characteristics for effective spark generation. By increasing the possibility of achieving sufficient sparks with lower power, efficiency and safety can be improved, and / or the intensity of effective IVL treatment can be reduced.

[0019] At block 40, an initial setting including an initial target voltage magnitude and a duration of voltage application is applied. As an illustrative example, a default initial setting is applied as a discharge voltage of 2500 volts (V) over a duration of 0.5 microseconds. In some embodiments, the initial setting may be determined by any suitable method, including using a programmable default as an application-based adjusted setting adjusted based on, among other aspects, patient characteristics, environmental conditions, treatment modalities, and / or product cycle life (i.e., operable time). From block 40, control may proceed to block 42.

[0020] In frame 42, IVL treatment is performed by applying electrical energy to spaced electrodes. In the first example, moving from frame 40 to frame 42, the electrical energy is applied with an initial setting, for example, an applied voltage of 2500V for a duration of 0.5 microseconds. When applied in a clinical setting, pressure wave therapy can then be performed with the IVL catheter positioned in the patient's body lumen, specifically with the discharge electrodes immersed in a fluid medium in a fluid-filled component such as an angiogenic balloon. However, as will be discussed below, under these conditions, the energy supplied in the initial setting may, in some cases, be insufficient to generate a spark at the electrodes, or may generate an insufficient spark or an insufficient pressure wave. From frame 42, control may proceed to frame 44.

[0021] In frame 44, the threshold current is determined. In one embodiment, the determination value of the current applied in frame 42 is compared with a predetermined threshold current value to determine and guarantee that an electric arc has been generated between separated electrodes. The predetermined threshold current value may be embodied as a predetermined fixed value, for example 20 amperes (amp), but in some embodiments, it may have any suitable value, for example 50 amperes, 100 amperes, 150 amperes, or 175 amperes. The threshold current value for a given cycle may be determined based, in particular, on the number of preceding cycles in a treatment session, the number of cycles maintaining the current settings in a treatment session (e.g., through frame 46), the number of specific consecutive cycles (e.g., consecutive cycles through frame 46 or frame 48 or frame 52 or frame 54 or frame 58), patient characteristics, environmental conditions, treatment method, and / or product cycle life (i.e., operating time). In addition, while the threshold current value may be set to a certain value, the actual current flowing during sufficient arc generation across the electrodes may be greater. Mechanisms for monitoring the applied current will be described further below.

[0022] If the current applied in frame 42 is judged to be equal to or greater than the threshold current value, the control may proceed to frame 46. Otherwise, if the current applied in frame 42 is judged to be less than the threshold current value, the control may proceed to frame 48. For example, as described above, if spark generation is insufficient, little or no current may be generated across the electrodes (e.g., about 0 to about 5 amperes, which may correspond to the energy dissipated into the medium without arc discharge), and the threshold current value will not be achieved, thus proceeding to frame 48.

[0023] In exemplary embodiments, the determination current value of the current applied in frame 42 is embodied as an instantaneous current applied across the electrodes and can be determined for each applied voltage pulse. In some embodiments, the determined current value may be embodied as an aggregate value, such as the time average of the current applied to the electrodes. Continuing with the exemplary embodiment applying a threshold current value of 20 amperes, when 20 amperes are achieved by the treatment being performed, it is determined that an electric arc has been generated, and the initial settings of voltage magnitude and duration are sufficient to generate the desired electric arc.

[0024] It can be recognized that a substantial current generation of 20 amps provides a considerable current across the discharge electrode, meaning the generation of a significant spark. In comparison, when a spark cannot be generated, or when an insufficient spark is generated under the applied duration and applicable voltage, for example, 2500V, it is possible that little to no current flows across the discharge electrode. The applicable voltage can generally range from about 500V to about 5000V for IVL treatment, but from a practical application standpoint, it may also be in the range of about 100V to about 10000V.

[0025] In frame 46, it is decided to maintain the currently selected settings. In an exemplary embodiment, the currently selected settings include the discharge voltage and applicable duration applied immediately before in frame 42. To avoid doubt, if an initial setting was applied immediately before in frame 42, resulting in a current of 20 amperes, that initial setting is applied to the next voltage pulse and / or cycle or continuation of voltage pulses. However, if the currently selected settings include updated settings, e.g., updated duration and / or voltage settings from the latter part of control 38, as described further herein, then maintaining the currently selected settings includes the updated settings applied immediately before. Maintaining the currently selected settings means openly proceeding back to frame 42 and again applying electrical energy to the electrodes to perform IVL treatment.

[0026] In frame 48, if the current threshold is not met, it is decided to increase the duration of the voltage applied to the discharge electrode. Continuing with the example where a current of less than 20 amperes means insufficient spark generation, the duration of the applied voltage can be increased progressively rather than immediately increasing the applied voltage. On a microsecond scale, increasing the duration of the applied voltage can increase the likelihood of sufficient spark generation using the same voltage that was applied up to that point. This can be achieved as a result of overcoming the threshold system impedance and / or other factors that affect the ease of spark generation during a given cycle at a given voltage.

[0027] The duration of the applied voltage may be incremented by predetermined duration intervals, which are exemplified by a fixed value, e.g., 0.5 microseconds, or other duration increments. In some embodiments, predetermined intervals with respect to a given voltage pulse and / or cycle or continuum of voltage pulses may be determined based on factors such as the number of treatment cycles performed up to that point during the treatment session (e.g., the number of intervals of voltage pulses, cycles, or continuums that have progressed through frames 42, 44, and 46 before proceeding to frame 48), patient characteristics, environmental conditions, treatment method, and / or product cycle life (i.e., operating time), among other embodiments. In some embodiments, predetermined duration intervals with respect to a given cycle may be varied by a predetermined rate of change, e.g., by a percentage gain or loss per cycle. The control 38 then openly proceeds from frame 48 to frame 50.

[0028] In frame 50, it is determined whether the maximum duration has been achieved. In some embodiments, the maximum duration is a predetermined duration that is embodied as a fixed value, for example, 35 microseconds or more. For example, if the control sequence proceeds in a cycle that starts from an initial setting of 0.5 microseconds in frame 40, passes through frame 48, and finally reaches an exemplary maximum value of 35 microseconds, the maximum duration is achieved as a threshold.

[0029] In some embodiments, the maximum duration of a given cycle may be determined based on, among other aspects, the number of preceding cycles in a treatment session, the number of cycles in a treatment session that maintain the current settings (e.g., through frame 46), the number of specific consecutive cycles (e.g., the number of consecutive cycles through frame 46 or frame 48 or frame 52 or frame 54 or frame 58), patient characteristics, environmental conditions, treatment method, and / or product cycle life (i.e., operating time). By reasoning, in frame 50, a positive determination and / or confirmation may be made that the threshold current value has not been achieved in the current cycle, although in some embodiments, the threshold current value has not been achieved. Depending on the determination that the maximum duration has not been achieved, control proceeds to frame 52. Otherwise, depending on the determination that the maximum duration has been achieved, control proceeds to frame 54.

[0030] In frame 52, it is decided to apply the updated duration and return to performing the treatment in frame 42. In an exemplary embodiment, the duration is updated in frame 48 by increasing the currently selected duration by a predetermined duration interval, and the decision to apply the updated duration confirms the updated duration and continues using it. In an exemplary embodiment, the applied voltage remains the same as the currently selected one. If continuing with the updated duration, openly proceed back to frame 42 and again apply electrical energy to the discharge electrode to perform the treatment using the updated duration.

[0031] In frame 54, the applied voltage is increased by a predetermined voltage interval. The currently selected setting of the applied voltage is increased by a predetermined voltage interval, as an example. The currently selected duration is reset to an initial value, exemplified as 0.5 microseconds, and applied along with the updated voltage. However, in some embodiments, the updated duration may have any preferred value under the newly updated voltage setting, for example, the updated duration may be determined based on the number of cycles in the treatment session when the newly updated voltage occurs.

[0032] In exemplary embodiments, a predetermined voltage interval is embodied as a fixed value of 250V, and at the first exemplary occurrence of frame 54, the currently selected applied voltage is increased from an initial value of 2500V to 2750V. In some embodiments, the predetermined voltage interval corresponding to a given cycle may be determined based, in particular among various embodiments, on the number of preceding cycles in a treatment session, the number of cycles in a treatment session that maintain the current setting (e.g., through frame 46), the number of specific consecutive cycles (e.g., the number of consecutive cycles through frame 46 or frame 48 or frame 52 or frame 54 or frame 58), patient characteristics, environmental conditions, treatment method, and / or product cycle life (i.e., operating time).

[0033] In frame 56, it is determined whether the maximum voltage has been achieved. In an exemplary embodiment, the maximum voltage is a predetermined voltage that is embodied as a fixed value, for example, 3500V. For example, if the control sequence proceeds in a cycle that starts from an initial setting of 2500V in frame 40, passes through frame 54, and finally reaches 3500V, the maximum voltage will be achieved as a threshold.

[0034] In some embodiments, the maximum voltage of a given cycle may be determined based on, among other embodiments, the number of preceding cycles in a treatment session, the number of cycles in a treatment session that maintain the current settings (e.g., through frame 46), the number of specific consecutive cycles (e.g., the number of consecutive cycles through frame 46 or frame 48 or frame 52 or frame 54 or frame 58), patient characteristics, environmental conditions, treatment method, and / or product cycle life (i.e., operating time). By reasoning, in frame 56, a positive determination and / or confirmation may be made that the threshold current value has not been achieved in the current cycle, although in some embodiments, the threshold current value has not been achieved. Depending on the determination that the maximum voltage has not been achieved, control proceeds to frame 58. Otherwise, depending on the determination that the maximum voltage has been achieved, control proceeds to frame 60.

[0035] In frame 58, it is decided to apply the updated voltage. In an exemplary embodiment, the voltage is updated in frame 54 by increasing the currently selected voltage by a predetermined voltage interval, and the decision to apply the updated voltage confirms the updated voltage and continues using it. The duration is updated in frame 45 to an exemplary initial value of 0.5 microseconds and is subsequently applied along with the updated applied voltage. If continuing with the updated voltage, the process proceeds openly back to frame 42, where power is again applied to the electrodes to perform treatment using the updated voltage and updated duration.

[0036] An error is detected in frame 60. An error message is provided in response to the error detection. Such an error message exemplifies terminating the treatment session, but in some embodiments, other safety actions and / or communication actions may be performed, for example, displaying the error communication to the user for consideration when deciding on corrective action.

[0037] In exemplary embodiments, inference may determine, in response to error detection, that the maximum voltage and maximum duration did not generate a spark; however, in some embodiments, insufficient spark generation may be determined. In some embodiments, in response to error detection, failed and / or insufficient spark generation under maximum voltage and maximum duration may be determined by active determination and / or confirmation. After frame 60, process control automatically terminates.

[0038] While the description of control 38 describes an exemplary increase in duration, in some cases, for example, in a particular cycle of control 38, the voltage level may be reduced. For example, the duration and / or voltage may be modified in accordance with control 38 in a given cycle so as to decrease progressively to achieve appropriate conditions, for example, to achieve appropriate discharge energy, in relation to consideration of the voltage levels of an energy storage system, such as a capacitive system, before and after discharge, as will be described in more detail herein.

[0039] As described later in this specification, the control system 22 may control the number of voltage pulses generated in one (or more) sequences of voltage pulses. The allowable voltage window comprises a predetermined starting voltage magnitude and a predetermined upper voltage magnitude. The IVL control system further comprises a predetermined voltage magnitude for progressively increasing the voltage magnitude after each sequence of voltage pulses, provided that the magnitude of the executed voltage pulse is within the allowable voltage window. However, for IVL systems with balloons of identifiable characteristics, such as different outer diameter size settings, e.g., 2.5 mm, 3.0 mm, 3.5 mm, and / or 4.0 mm, a separate set of predetermined control data may be provided within the control system 22.

[0040] An exemplary embodiment may include a 2.5 mm or 3.0 mm balloon, in which case the control system 22 includes control data including an exemplary starting target voltage (a predetermined lower voltage threshold) of about 3000 V, a sequence of voltage pulses comprising 10 pulses, and a gradual voltage increase of 25 V if the magnitude of the sequence of voltage pulses is less than an exemplary upper voltage threshold of about 3500 V. As will be recognized by those skilled in the art, the gradual voltage increase may consist of any voltage magnitude, but is not limited to, including within about 1 V to about 250 V. A preferred voltage increase may include about 25 V, but in a particular embodiment it may be greater or less than 25 V. As will be recognized by those skilled in the art, the predetermined starting voltage may be less than 3000 V, and the predetermined upper voltage threshold may be greater than 3500 V. Thus, the exemplary starting voltage may include, but is not limited to, about 2500 V, and the exemplary upper voltage threshold may include about 4100 V. In other embodiments, the exemplary predetermined starting voltage may be greater than 3000V, and the exemplary upper voltage threshold may be greater than approximately 3250V.

[0041] Other exemplary embodiments may include a 3.5 mm or 4.0 mm balloon, in which case the control system 22 includes control data including an exemplary starting target voltage of 2850 V (a predetermined lower voltage threshold), a sequence of voltage pulses comprising 10 pulses, and a gradual voltage increase of 25 V if the magnitude of the sequence of voltage pulses is less than an exemplary predetermined upper voltage threshold of 3700 V.

[0042] Other exemplary embodiments may include 2.5 mm, 3.0 mm, 3.5 mm, or 4.0 mm, in which case the control system 22 includes control data including an exemplary predetermined start target voltage of about 2850 V and an exemplary upper voltage threshold of about 3250 V.

[0043] In some embodiments, the control system 22 may include an exemplary predetermined starting voltage magnitude and an exemplary upper voltage threshold in the range of about 2700V to about 3700V.

[0044] In some embodiments, the current generated by the voltage pulse may be in the range of 120 amperes to 220 amperes.

[0045] In some embodiments, a sequence of voltage pulses may be generated and sent to one or more sets of spaced electrodes 18, followed by a pause in the generation of voltage transmission. Certain embodiments may include a pause between the last pulse in the sequence of voltage pulses and the first pulse in the sequence immediately following the voltage pulse, the pause being in the range of 5 to 20 seconds. More preferably, the pause between adjacent sequences of voltage pulses may be about 10 seconds.

[0046] Some embodiments may include a predetermined time gap or duration between adjacent voltage pulses in a sequence of voltage pulses. In some embodiments, the time gap or duration between adjacent voltage pulses in a sequence of voltage pulses may be in the range of about 0.25 seconds (corresponding to a voltage pulse frequency of about 4 Hz) to about 1 second (corresponding to a voltage pulse frequency of about 1 Hz).

[0047] In some embodiments, the preferred time gap or duration between adjacent voltage pulses in a sequence of voltage pulses may be about 0.5 seconds (corresponding to about 2 Hz).

[0048] In some embodiments, the predetermined duration pause between adjacent voltage pulses may be longer in length or duration than the time gap or duration between adjacent voltage pulses in a sequence of voltage pulses.

[0049] In some embodiments, the width or duration of the applied voltage pulse may be in the range of about 20 to about 30 microseconds. In some embodiments, the width or duration of the applied voltage pulse may be about 25 microseconds.

[0050] In some embodiments, a predetermined number of voltage pulses in a sequence of voltage pulses may be in the range of 5 to 20 or more voltage pulses. In some embodiments, the number of voltage pulses in a sequence of voltage pulses may be approximately 10 voltage pulses.

[0051] In some embodiments, the predetermined maximum number of voltage pulses allowed in any one of the catheter assemblies 14 may be in the range of 50 voltage pulses to 300 or more voltage pulses.

[0052] Each control data, including at least a predetermined starting voltage, an upper voltage threshold, the width or duration of the generated and / or applied voltage pulses, a predetermined pause between consecutive adjacent voltage pulses, a time gap between adjacent voltage pulses in a sequence of voltage pulses, the number of generated voltage pulses required before the voltage is increased, the magnitude of the voltage increase, and / or the maximum number of voltage pulses allowed for a given catheter assembly 14, is stored in the control system 22 and may be executed by the control system 22.

[0053] In other embodiments, as will be described later, an EPROM device well known in the art may be connected to or associated with a handle operationally coupled to the catheter assembly. In these embodiments, control data including at least a predetermined start voltage, an upper voltage threshold, a predetermined pause between consecutive adjacent voltage pulses, a time gap between adjacent voltage pulses in a sequence of voltage pulses, and / or the maximum number of voltage pulses allowed for a given catheter assembly 14 may be stored in the EPROM operationally coupled to the control system 22. The EPROM may enable the identification of a particular catheter assembly 14 that may require its own individualized control dataset, thus enabling highly flexible operation.

[0054] In various embodiments, the control system 22 may monitor data corresponding to control data, and if the monitored data does not conform to a range of stored values ​​or is within a threshold, the control system 22 may notify the operator, and in some embodiments, may not allow the generation of further voltage pulses.

[0055] Continuing with reference to Figures 1, 2, 3A, and 3B, several parts of an exemplary electrical pulse generation system 20, including several parts of the IVL control system 22, are disclosed herein, which include various functions and / or circuits that may be implemented as part of a circuit 28. In some embodiments, such systems 20, 22 may, as appropriate, have components that share and / or separate components, for example, the circuit 28, which is intended to be schematic, may represent a circuit embodied by system 20 alone. In exemplary embodiments, the IVL control system 22 includes an adjustable energy storage system 112, such as an exemplary capacitance system, as an example, to selectively adjust the energy storage capacity or magnitude applied to supply electrical energy to the electrodes. Hereinafter, we will refer to the energy storage system 112, which will be described by but not limited to a capacitance system.

[0056] The energy storage system 112 receives charging electrical energy from the power source of the electrical pulse generation system 20. The energy storage system 112 supplies discharge electrical energy to the electrodes (e.g., via VCAP2 and ground, as illustrated herein) as described in more detail herein.

[0057] The adjustable energy storage system 112 includes, as an example, several, e.g., one or more energy storage units, which are exemplified as individual capacitors 114, forming an energy storage network. In exemplary embodiments, each energy storage unit 114 may be of the same size having the same energy storage capacity and may be arranged to be connected in parallel with other energy storage units in the energy storage network, but in some embodiments, any size and / or arrangement of energy storage units may be provided to support variable energy storage for IVL treatment. A relay system 116 may be arranged in association with at least some of the energy storage elements 114 of the network. The relay system 116 comprises one or more relays for selectively connecting the energy storage elements 114 to each other to receive charge and release electrical energy to electrodes.

[0058] In an exemplary embodiment, the relay system 116 includes a coupling configuration in which all energy storage elements 114 of the network are connected for use in IVL. When connected for use in IVL, the energy storage elements 114 may be connected to other parts of the electrical pulse generation system 20 to exchange electrical energy under other control operations. For example, under a typical charge control operation, the energy storage elements 114 connected by the relay system 116 for use in IVL may receive charge from a power source, and / or, under a typical discharge control operation, the energy storage elements 114 connected by the relay system 116 for use in IVL may supply discharge energy to the electrodes 18. Thus, it can be recognized that the relay system 116 can selectively connect all energy storage elements 114 for use in IVL treatment to result in the largest possible energy storage size.

[0059] In addition, the relay system 116 includes a non-coupled configuration in which fewer energy storage elements than the total energy storage elements 114 of the network are connected for use in IVL, as indicated in Figures 4A–4D. For ease of explanation, several energy storage elements 114, two in particular, are depicted as being disconnected from other energy storage elements by the disconnection of the relay system 116, but this is not limited to them. Energy storage elements 114 disconnected for use in IVL by the relay system 116 cannot receive charge from the power source and / or, under typical discharge control operation, energy storage elements 114 disconnected for use in IVL by the relay system 116 cannot supply discharge energy to the electrode 18. Energy storage elements disconnected for use in IVL treatment may be discharged separately from the electrode via a diode 118 placed in parallel with the relay system 116, for example (e.g., for a safe reduction of stored power).

[0060] It can be recognized that the total amount of energy supplied to the electrodes can be controlled by adjusting the energy storage capacity available for supplying electrical energy to the electrodes. The stored energy is

[0061]

number

[0062] In an exemplary embodiment, the IVL control system 22 is configured to control the applied stored energy. For example, the IVL control system 22 determines the amount of stored energy to be applied, and if it determines that a change in the magnitude of the energy stored is desired, the IVL control system 22 operates the relay system 116 accordingly. For example, the IVL control system 22 may determine that a lower magnitude of energy stored is desired and / or required for a certain voltage pulse, and may communicate to the relay system 116 to operate in an uncoupled configuration.

[0063] For one or more subsequent voltage pulses, the IVL control system 22 may determine that a larger energy storage size is desired and / or required for another voltage pulse and may communicate to operate the relay system 116 in coupled configuration. For one or more further subsequent voltage pulses, the IVL control system 22 may again determine that a lower energy storage size is desired and / or required and may return the relay system 116 to uncoupled configuration. Thus, the IVL control system 22 may operate the relay system 116 as needed to provide an adjustable energy storage size for any given voltage pulse in a sequence of voltage pulses.

[0064] The applied energy storage may be adjusted as it progresses, for example, for any given pulse. In practice, the adjustment of the energy storage capacity or size may be done in relation to the level of the applied voltage and / or taking into consideration power, efficiency, and / or other aspects of the technology. Furthermore, under the lifetime of the applied device and system, normal wear of components may change their electrical and / or physical properties, which may benefit from the adjustment of the applied energy storage. For example, even slight wear of electrodes may change the gap between pairs of electrodes, which may change the conditions of the arc between the electrodes. Thus, the size of the adjustable energy storage can address variations in parts of electrodes and / or discharge systems under repeated use, whether in individual treatment sessions or otherwise.

[0065] Continuing with reference to Figures 3A and 3B, embodiments of the present disclosure relate to systems and methods for regulating a voltage supplied to charge an energy storage system 112 as a charging voltage. The charging voltage is supplied, exemplarily, as an input to the energy storage system 112 as an energy storage, which is released to generate controlled voltage pulses for variable charging. The charging voltage is controlled, exemplarily, by a charging control system 120 of an IVL control system 22.

[0066] In an exemplary embodiment, the charge control system 120 provides high-precision control of the charging voltage via a high-frequency switched control signal from the processor 24. The switched control signal ("HVIN_VSET") is embodied, exemplarily, as a pulse-width modulation (PWM) signal and amplified for control of the high-voltage supply. The high-voltage DC / DC conversion system 122 receives instructions for the switched control signal in the range of approximately 0V to approximately 12V and supplies a corresponding charging voltage in the range of approximately 0V to approximately 4000V, exemplarily.

[0067] In the illustrated embodiment, the charge control system 120 includes a buck regulator system 124 for conditioning low-voltage power. The buck regulator system 124 is embodied, exemplarily, as an integrated circuit (IC) that provides signal conditioning by low-pass filtering and buffering of the PWM signal. The buck regulator system 124 receives the conditioned PWM signal with feedback to supply controlled low-voltage power to the conversion system 122 for applying high-voltage power.

[0068] Resistor 126 can appropriately reduce the feedback voltage for IC operation, supplying a variable feedback voltage in the range of approximately 0V to approximately 3.3V to the buck regulator system 124 via an additional resistor 128. As the duty cycle of the PWM signal increases from 0 percent to 100 percent, the filtered signal increases from 0 volts to 3.3 volts, thereby increasing the current supplied to the feedback network, and also allowing for lower voltages to be required to achieve adjustment in resistors, inductors, and / or capacitors placed, for example, between the buck regulator system 124 and the conversion system 122.

[0069] Continuing with reference to Figures 3A and 3B, embodiments of the present disclosure relate to systems and methods for controlling the effective time of discharge voltage pulses supplied to electrodes. A switching signal (e.g., "GATE_PULSE") is provided by the processor 24 for high-voltage switching via low-voltage signaling. In exemplary embodiments, the switching signal is applied to operate a discharge switch system 130 with high precision. The discharge switch system 130 is embodied, exemplarily, to implement a driver 131 as a gate switch and a semiconductor device 132.

[0070] The gate switch 132 is embodied, for example, as an insulated-gate bipolar transistor (IGBT) having an n-type gate control configuration. When the switching signal to the driver 131 is active, the gate switch 132 is activated and energized, transferring the release of energy from the energy storage system 112 to the electrodes. When the switching signal is inactive, the gate switch 132 is deactivated and non-conductive, preventing the release of energy from the energy storage system 112 to the electrodes.

[0071] In exemplary embodiments, the gate switch 132 is configured as an active-high device, but in some embodiments, it may be implemented as an active-low device. The gate-controlled, active-high IGBT can provide high-precision control of the release from the energy storage system 112, but may be implemented in any preferred manner, including by other suitable semiconductors (e.g., p-type, FET, etc.) and / or other control designs (e.g., current collector, emitter control, etc.).

[0072] In exemplary embodiments, the discharge switch system 130 includes an antiparallel diode 134 arranged to reduce reverse voltage stress on the gate switch 132. A deactivation signal ("HV_DISABLED") is provided to the driver 131, which, under the direction of the processor 24 and / or other safety systems, may allow the release of energy to the electrodes with an inactive (low) signal, or activate (high) to disable high-voltage discharge. The snubber system 136 is embodied, exemplary, as a resistor-capacitor-diode (RCD) snubber network arranged to reduce voltage transitions that may exceed the rated voltages of various high-voltage components.

[0073] Referring next to Figures 4A to 4D, the IVL control system 22 includes, as an example, a power monitoring system 140. The power monitoring system 140 is configured to monitor various power parameters of the IVL device and system, including, as an example, sensing the current and voltage supplied to the electrodes, as well as the voltage of the adjustable energy storage system 112.

[0074] The power monitoring system 140 includes, as an example, a current monitoring system 142. The current monitoring system 142 is embodied to sense the current supplied to an electrode for a given voltage pulse. As described further in this specification, the current supplied to the electrode can be taken into consideration when determining the power characteristics of the subsequent voltage pulse.

[0075] In the exemplary embodiments shown in Figures 4A-4D, the current monitoring system 142 receives an indication of the voltage level applied with each voltage pulse to determine the current delivered to the electrodes. Returning temporarily to Figures 3A and 3B, a shunt 138 is positioned in the high-voltage current path to establish proportional voltages (e.g., "VCURR+", "VCURR-"). These proportional voltages are communicated to the current monitoring system 142 as shown in Figures 4A-4D.

[0076] A chip containing amplifier 144 is positioned to increase or decrease the proportional voltage and provides the analog result to a conditioning network 146, which is embodied by including a resistor-capacitor network for scaling and / or filtering. The conditioning signal is buffered by a buffer amplifier 148, and its output is provided to an analog-to-digital converter (ADC) system 150 for digital conversion.

[0077] The ADC system 150 includes, as an example, a transducer 152 and a memory 154. In the exemplary embodiment, the transducer 152 provides a digital output from an analog input, and the memory 154 is embodied as a first-in, first-out (FIFO) device for intermediate storage of the digital output. The memory 154, as an example, receives the same clock signal that drives the transducer 152, enabling rapid sampling of several measurement points with low jitter. The memory output is provided to the processor 24 for consideration in overall IVL treatment control.

[0078] The IVL control system 22 includes, as an example, a current monitoring system which compares an output signal ("VCURR") generated by a chip comprising amplifier 144 with a threshold. The threshold is embodied to be generated by a variable duty cycle PWM signal ("ISNS_ISET") from processor 24. The PWM signal may be low-pass filtered and / or buffered before being sent to a comparator. Depending on whether the measured current exceeds the threshold, the current monitoring system may assert an error signal (e.g., "ISNS OVER#") to avoid an overcurrent condition.

[0079] The power monitoring system 140 includes, as an example, a voltage monitoring system 170. The voltage monitoring system 170 is embodied to sense the voltage between a set of electrodes. As will be described in more detail herein, the voltage between electrodes for a given pulse may be taken into consideration when determining the power characteristics of a subsequent voltage pulse.

[0080] In an exemplary embodiment, the voltage monitoring system 170 includes a resistor network 172 arranged to attenuate the voltage (e.g., "VCAP1") of one of a pair of electrodes. The attenuated signal is provided to an operational amplifier network 174 for filtering and offsetting before outputting to a digital conversion. The output from the operational amplifier network 174 is provided to an ADC conversion system 176 for digitization, which includes storing it in a FIFO memory 178 for access by the processor 24.

[0081] The power monitoring system 140 may, as an example, include an energy storage capacity voltage monitoring system 180 configured to monitor the voltage within an adjustable energy storage system 112. By monitoring the voltage of the energy storage system 112, it may be possible to determine the stored energy of the energy storage system 112. Furthermore, a comparison of the stored energy of the energy storage system 112 before and after discharge can provide an indication of the total energy delivered during a given discharge cycle. Considering such total energy data can increase confidence in determining whether a sufficient spark was generated for IVL treatment.

[0082] In an exemplary embodiment, the voltage monitoring system 180 includes a voltage limiting system configured to monitor the net voltage of the energy storage system 112 during charging. In an exemplary embodiment, the voltage monitoring is described in relation to the connected energy storage element 114, more specifically, the energy storage element connected to supply controlled discharge energy for IVL treatment, and not to the energy storage element that is disconnected via the relay system 116, if present.

[0083] The voltage monitoring system 180 receives an indication of the voltage of the energy storage system 112 during charging ("VCAP1"). System 180 includes, as an example, an amplifier configuration 182 comprising an amplifier 184 and a comparator 186. The comparator 186 is, as an example, configured to compare the voltage to a fixed voltage and trigger a signal (e.g., "VCAP1_OVER#") accordingly if the voltage of the energy storage system 112 exceeds the fixed voltage. In the exemplary embodiment, the fixed voltage is embodied as a setpoint generated by a resistor-resistance-capacitor network 188, which is above normal operation but is a value before damage occurs to various HV components.

[0084] The intermediate voltage of this circuit (e.g., "AN_VCAP1") can be used to monitor the progress of the energy storage system 112 during its charging cycle. The intermediate voltage, as an example, represents a significantly attenuated version of the high voltage ("VCAP_1") supplied to the electrodes by the energy storage system. Such an attenuated signal allows for monitoring of the high-voltage system while processing low-voltage indications from the high-voltage system.

[0085] Referring next to Figure 5, and then to Figures 1 and 3, the IVL system 12 can take into account the energy of the energy storage system 112 during operation. By monitoring the energy of the energy storage system 112 before and after a discharge event, it is possible to determine the instructions for spark generation (and / or sufficiency), as will be further described with reference to the exemplary embodiment with reference to the operation 300 relating to frames 312-322.

[0086] In the frame 312, the energy storage system 112 is evaluated. In an exemplary embodiment, this evaluation includes determining the voltage of the energy stored by the energy storage system 112. As described above, the voltage monitoring system 180 can monitor the voltage of the energy storage system 112 during charging, for example, via a voltage limiting system. In some embodiments, the evaluation may include determining any other suitable parameters that assist in energy monitoring of the energy storage system 112.

[0087] In frame 314, the energy of the energy storage system 112 is determined. In an exemplary embodiment, the energy of the energy storage system 112 is

[0088]

number

[0089] In frame 316, IVL treatment can be attempted. In exemplary embodiments, a voltage pulse may be sent to the electrode. The voltage pulse can be applied according to a control mechanism described herein, for example, based on a determined duration in a control sequence.

[0090] In frame 318, the energy storage system 112 is evaluated. The evaluation of the energy storage system 112 in frame 218 is embodied to be performed immediately after the IVL treatment attempted in frame 216 in order to provide indication of the energy state of the energy storage system 112 immediately after the release (attempted release) to the electrodes. In exemplary embodiments, the evaluation includes determining the voltage of the energy stored by the energy storage system 112, which is embodied to be performed by voltage monitoring as described above, but in some embodiments, the evaluation of the energy storage system 112 in frame 318 may differ from that in frame 312 in methodology and / or practice.

[0091] In frame 320, the energy of the energy storage system 112 is determined. In an exemplary embodiment, the energy of the energy storage system 112 is determined here as in frame 214.

[0092]

number

[0093] In frame 322, a comparison of energy determinations is performed. The amount of energy determined in the energy storage system 112 in frame 314 is subtracted, as an example, from the amount of energy determined in the energy storage system 112 in frame 320, and the result represents the amount of energy released from the energy storage system 112 in one attempt to perform IVL treatment.

[0094] By considering the amount of energy released, it is possible to determine whether a spark (or sufficient spark) has occurred to trigger IVL treatment. In exemplary embodiments, threshold energy release represents the released energy level that reliably indicates that a sufficient spark has occurred in the IVL. Thus, in frame 322, comparing the stored energy levels before and after the release to determine whether threshold energy release has been achieved can indicate a spark for IVL treatment.

[0095] In an exemplary embodiment, referring to Figure 2, the threshold energy release is a fixed predetermined value, for example, 600 millijoules (e.g., 3700 V, 90 nanofarads). However, in some embodiments, the threshold energy level of a given cycle may be determined based on, among other embodiments, the number of preceding cycles in a single treatment session, the number of cycles maintaining the current setting in a single treatment session (e.g., through frame 46 in Figure 2), the number of specific consecutive cycles (e.g., the number of consecutive cycles through frame 46 or frame 48 or frame 52 or frame 54 or frame 58), patient characteristics, environmental conditions (e.g., position within the patient's body, such as above the knee or above the knee), treatment method, and / or product cycle life (i.e., operating time).

[0096] A comparison of the energy levels in the energy storage system 112, indicating that a spark for IVL treatment has occurred, can in response produce further treatment with the same duration, energy level, threshold characteristics, and / or a threshold adjusted to suit other parameters. A comparison of the energy levels in the energy storage system 112, indicating that a spark for IVL treatment has not occurred, can result in adjustments to the duration and / or the applied energy level, as described, for example, with respect to control operation 38.

[0097] In some embodiments, the threshold current value can be applied together with the threshold energy release, and either threshold can individually indicate a spark for IVL treatment. In some embodiments, it may be necessary for both thresholds to be satisfied in order to indicate a spark for IVL treatment.

[0098] Considering the energy state of the energy storage system 112 can provide desirable monitoring of IVL operation. For example, such monitoring can be less intrusive by reducing the need for direct measurement at electrodes. Furthermore, in high-power applications, reliable consideration of the energy state can promote reliability compared to mere direct measurement in unpredictable high-energy arc scenarios.

[0099] The IVL control system 22 includes, as an example, an external watchdog system configured to support safe operation. The watchdog system includes an integrated circuit configured to trigger an error when an input signal that can be switched in a timely manner is absent, thereby ensuring proper high-voltage operation. In some embodiments, the watchdog system may be formed externally, including a processor, memory, and / or circuitry, either separate from or shared with the IVL control system 22.

[0100] Returning to Figures 3A and 3B, in an exemplary embodiment, the IVL control system 22 includes an umbrella monitoring system 190 configured to support safe operation. The umbrella monitoring system 190 includes, as an example, a flip-flop 192 and a logic gate 194 for considering monitoring signals. The logic gate 194 is configured to receive a high voltage warning ("HV_WD0#") from the watchdog system, which is a monitoring signal embodied as an energy storage system overvoltage ("VCAP1_OVER#") from the voltage monitoring system 180, and in some embodiments, it may also receive an overcurrent ("ISNS_OVER#") from the current monitoring system.

[0101] Logic gate 194 is implemented as an AND gate, and flip-flop 192 is implemented as an asynchronous D flip-flop. An activation signal from gate 194 that lasts longer than the minimum clock pulse width of flip-flop 192 will cause the output to assert and disable the high-voltage output (e.g., "HV_DISABLED"), but an activation signal from gate 194 that lasts shorter than the minimum clock pulse width of flip-flop 192 will not raise the disable output from umbrella monitoring system 190.

[0102] Asserting a signal to disable the high-voltage output ("HV_DISABLED") is provided, for example, to the discharge switch system 130 to disable the activation of the voltage pulse switch to the electrodes. In an exemplary embodiment, the disable output signal is provided to the driver 131 to indirectly change the on / off operation of the gate switch 132. Such a disable output signal is provided, for example, to a low-voltage source, e.g., a buck regulator system 124, and a high-voltage module, e.g., a conversion system 122.

[0103] Therefore, the logic gate 194 receives the aforementioned monitoring signals, including (1) an energy storage system overvoltage ("VCAP1_OVER#") from the voltage monitoring system 180, and (2) a high voltage warning ("HV_WD0#") from the watchdog system, and in some embodiments, it may also receive (3) an overcurrent ("ISNS_OVER#") from the current monitoring system. These monitoring signals are also connected to a 3-input AND logic gate [U12], which is upstream of a D flip-flop [U15] having asynchronous setting and resetting capabilities, so that any signal asserted for longer than the minimum pulse width of the flip-flop [U15] will assert its output [HV_DISABLED, HV_DISABLED#]. These signals travel downstream to block the operation of the gate driver [U11], the variable low-voltage source [U6], and the high-voltage module [U7], and slightly alter the on / off operation of the switching devices [Q10, Q11] via transistors [Q12, Q13]. The system can be disabled by any of the monitoring signals if asserted for longer than an established duration.

[0104] In this disclosure, the ability to disconnect either the AC mains power or the battery DC power can provide versatility in power and control for IVL treatment. Unlike known IVL systems, certain embodiments of this disclosure can avoid remaining idle until fully (or substantially) recharged for application in IVL treatment, for example, if the battery is not sufficiently charged by the time the IVL treatment is desired. Thus, such costly delays or interruptions in the procedure can be avoided by embodiments of this disclosure. The electrical pulse generation system 20 includes, exemplarily, a battery power storage system and is configured to selectively charge the energy storage system 112 solely by the battery's stored energy, or by the battery power storage system while connected to a mains power source such as a wall outlet, or directly with DC power converted from the AC mains power source without using the battery power storage system. When connected to an AC mains power source, regulated DC power is sent directly to the high-voltage system. In operating conditions where the power demand for IVL operation is high, the charging current to the battery power storage system can be reduced to allow for a higher system current for IVL operation. When not connected to an AC mains power source, battery power can be sent directly to the energy storage system 112. In exemplary embodiments, power management systems and devices, including, for example, inverters, regulators, energy storage devices, and / or related embodiments, may be comprised of an electrical pulse generation system 20 that supplies applicable power to an IVL control system 22.

[0105] Examples of suitable processors may include, among other things, one or more microprocessors, integrated circuits, and system-on-a-chip (SoCs). Examples of suitable memory may include, among other things, one or more main memory and / or non-main memory (e.g., secondary, tertiary, etc.); permanent, semi-permanent, and / or temporary memory; and / or, but not limited to, memory storage devices including hard drives (e.g., magnetic, solid state), optical disks (e.g., CD-ROM, DVD-ROM), RAM (e.g., DRAM, SRAM, DRDRAM), ROM (e.g., PROM, EPROM, EEPROM, flash EEPROM), and volatile and / or non-volatile memory. The communication circuit 58 includes components to facilitate the operation of the processor, and for example, suitable components may include transmitters, receivers, modulators, demodulators, filters, modems, analog-to-digital (AD or DA) converters, diodes, switches, operational amplifiers, and / or integrated circuits. In some embodiments, memory 26 may represent one or more memory devices capable of operating for IVL therapeutic operations. For example, each memory (e.g., 154, 178) may be included as part of memory 26, shared with it, or separate from it.

[0106] In this disclosure, the consideration of a set of discharge electrodes is described in the context of a pair of electrodes, but in certain cases one of them may function as a cathode and the other as an anode. However, the number of electrodes in a set may be greater than one pair, and may include, for example, one or more cathodes in contact with one or more anodes. In addition, the apparatus, systems, and methods in this disclosure may include two or more groups of connected electrodes, which may be arranged electrically in series, in parallel, or independently of each other.

[0107] The power control operations disclosed herein may be applied equally, simultaneously, and / or sequentially to individual sets or groups of electrodes in a given IVL treatment cycle. For example, a threshold current value may be applied collectively to all deployed electrodes or to individual groups or sets of electrodes. Decisions made with respect to power control may be applied equally to the relevant electrodes in a given IVL treatment cycle or to individual groups or sets of electrodes. In this disclosure, supporting components such as power supplies, sensors, and other mounting structures, and / or functions for performing IVL operations as disclosed herein, are embodied as sub-parts of the electrical pulse generation system 20 and / or the IVL control system 22, for example, as part of circuits and / or instructions.

[0108] Referring next to Figure 6, another embodiment of control 200 in the operation of one embodiment of the IVL system is shown, specifically an exemplary flowchart relating to the number of voltage pulses generated and the magnitude of the pulses generated. It will be understood that control 200 may be combined with embodiments of the control systems and methods described above in relation to Figures 1-5.

[0109] The control operation of control 200 may be controlled by the electrical pulse generation system 20 and by the IVL control system 22, as illustrated above in relation to Figure 1. As further described herein, the control system 22 may control the number of voltage pulses generated in one (or more) sequences of voltage pulses. The allowable voltage window comprises a predetermined starting voltage magnitude and a predetermined upper voltage magnitude. The IVL control system further comprises a predetermined voltage magnitude for progressively increasing the voltage magnitude after each sequence of voltage pulses, provided that the magnitude of the executed voltage pulse is within the allowable voltage window. For IVL systems with balloons of identifiable characteristics, such as different size settings, e.g., 2.5 mm, 3.0 mm, 3.5 mm, and / or 4.0 mm, a separate set of predetermined control data may be provided within the control system 22.

[0110] An exemplary embodiment of the IVL system may include a 2.5 mm or 3.0 mm balloon, in which case the control system 22 includes control data including an exemplary starting target voltage of 3000 V (a predetermined lower voltage threshold), a sequence of voltage pulses comprising an exemplary 10 pulses, and an exemplary gradual voltage increase of 25 V if the magnitude of the sequence of voltage pulses is less than an exemplary upper voltage threshold of 3500 V. A person skilled in the art will recognize that the gradual voltage increase may be of any magnitude, including, but not limited to, 1 V to 250 V. The exemplary voltage increase may include 25 V, but in a particular embodiment it may be greater or less than 25 V. As a person skilled in the art will recognize, the predetermined starting voltage may be less than 3000 V, and the predetermined upper voltage threshold may be greater than 3500 V. Thus, the exemplary starting voltage may include, but not limited to, 2500 V, and the exemplary upper voltage threshold may include 4100 V. In other embodiments, the exemplary predetermined starting voltage may be greater than 3000V, and the exemplary upper voltage threshold may be greater than 3250V.

[0111] Other exemplary embodiments may include a 3.5 mm or 4.0 mm balloon, in which case the control system 22 includes control data including an exemplary starting target voltage of 3250 V (a predetermined lower voltage threshold), a sequence of voltage pulses comprising 10 pulses, and a gradual voltage increase of 25 V if the magnitude of the sequence of voltage pulses is less than an exemplary predetermined upper voltage threshold of 3700 V.

[0112] Continuing with reference to Figure 1, and in some embodiments to Figure 2, Figure 6 shows the start of the voltage pulse generation and control system 200, which starts in frame 202, where it is necessary to determine the specific balloon characteristics of the subject, e.g., the outer diameter ("OD") of the balloon in the IVL system. In the first embodiment, if the outer diameter of the balloon is, for example, 2.5 mm or 3.5 mm, the starting voltage is set to 3000 V in frame 204, which is also referred to as a predetermined lower voltage threshold of the allowable voltage magnitude window. The IVL treatment is started in frame 206 by applying a series of voltage pulses (or shocks) from the electrical pulse generation system 20, with each voltage pulse traveling to the electrode 18 in the balloon 16. In frame 208, if the magnitude of the target voltage is not a predetermined upper voltage threshold, e.g., 3500 V, the target voltage is increased by an exemplary 25 V (from 3000 V to 3025 V), as in frame 109, and another series of voltage pulses (10 pulses in this case) is performed at 3025 V, as in frame 210. This process continues, repeating between frames 208, 209, and 210, until the target voltage reaches 3500V. When the target threshold voltage, i.e., a predetermined upper voltage threshold, is reached, and / or, in some embodiments, when a predetermined maximum or required number of voltage pulses, e.g., 300 pulses (or shocks), is generated, the control system 22, as shown in frame 212, determines whether the number of generated voltage pulses (or shocks) in a series of voltage pulses has reached the maximum or required number of pulses, e.g., 300 voltage pulses. If the maximum or required voltage pulse threshold, e.g., 300 voltage pulses, has not been reached, another series of voltage pulses (or shocks), e.g., 10 voltage pulses (or shocks), is applied, as shown in frame 214. When the maximum or required voltage pulse threshold, e.g., 300 voltage pulses, is reached, no further voltage pulses (or shocks) are allowed, as shown in frame 216.

[0113] The predetermined maximum number of voltage pulses in various embodiments of this disclosure may be in the range of 10 to 300 voltage pulses. The exemplary embodiments described herein have a predetermined maximum number of voltage pulses equal to 300 pulses. In other embodiments, the maximum number of voltage pulses may be greater than 300 pulses.

[0114] In the second embodiment, continuing with reference to Figure 1, and in some embodiments to Figure 2, if the outer diameter of the balloon is determined to be, for example, 3.5 mm or 4.0 mm in frame 202, the electrical pulse generation system 20 initiates treatment in frame 118, with the initiation voltage set to 3250 V, which is also referred to as a predetermined lower voltage threshold of the allowable voltage magnitude window. IVL treatment is initiated in frame 220 by applying a sequence of voltage pulses from the electrical pulse generation system 20, each voltage pulse traveling to the electrode 18 in the balloon 16. In frame 222, if the magnitude of the target voltage is not a predetermined upper voltage threshold, for example, 3500 V, the target voltage is increased by an exemplary 25 V (from 3250 V to 3275 V), as in frame 223, and another sequence of voltage pulses (10 pulses in this case) is performed at 3275 V, as in frame 224. This process continues, repeating between frames 222, 223, and 224, until the target voltage reaches 3700 V. When a target threshold voltage, or a predetermined upper voltage threshold, is reached, and / or, in some embodiments, when the maximum or required number of pulses, e.g., 300 pulses (or impacts, if applied to one or more pairs of spaced electrodes), is generated, the control system 22 determines, as shown in frame 212, whether the number of generated voltage pulses (or impacts) in a series of voltage pulses has reached the maximum or required number of pulses, e.g., 300 voltage pulses. If the maximum or required voltage pulse threshold, e.g., 300 voltage pulses, has not been reached, another series of voltage pulses (or impacts), e.g., 10 voltage pulses (or impacts), is applied, as shown in frame 214. If the maximum or required voltage pulse threshold, e.g., 300 voltage pulses, is reached, no further voltage pulses (or impacts) are allowed, as shown in frame 216.

[0115] Alternatively, a physician performing IVL treatment according to the voltage pulse generation and control system 200 may determine at some point during the treatment that the treatment is complete. If the treatment is determined to be complete, the physician may terminate the process of the voltage pulse generation and control system 200 at any time.

[0116] In some embodiments, the voltage pulse generation and control system 200 may include a change in the duration of the applied voltage in or across one or more sequences of voltage pulses, as described above in relation to Figure 2. For example, the duration may be increased or decreased by a predetermined duration interval, which may be embodied as a fixed value, e.g., 0.5 microseconds. In some embodiments, the predetermined interval for a given cycle may be determined based on factors such as the number of treatment cycles performed up to that point during a treatment session (e.g., the number of sequences of voltage pulses performed by proceeding through frames 206, 208, and 210, or 220, 222, and 224), patient characteristics, environmental conditions, treatment method, and / or product cycle life (i.e., operating time), among other embodiments. In some embodiments, the predetermined duration interval for a given cycle may be changed by a predetermined rate of change, e.g., a percentage gain or loss per cycle.

[0117] Figure 7 shows a schematic comparison between a known IVL apparatus (publicly known) equipped with 2.5 mm and 4.0 mm OD balloons and the IVL apparatus (test) according to this disclosure, equipped with 2.5 mm and 4.0 mm OD balloons.

[0118] Known devices are capable of generating 80 voltage pulses or shocks. The test device generated 300 voltage pulses or shocks. During the comparative test, the magnitude of the voltage peak was obtained for each voltage pulse and plotted for each device tested. Known devices provide a relatively flat or constant voltage for each voltage pulse or shock count and start with a lower voltage magnitude than the test device. The test device was operated and controlled according to the embodiments disclosed herein.

[0119] In contrast, each of the 2.5 mm and 4.0 mm test apparatuses starts at a higher voltage magnitude than the known apparatus. The 2.5 mm test apparatus starts at a lower voltage than the 4.0 mm apparatus. As shown in the figure, the voltages of both the 2.5 mm and 4.0 mm test apparatuses (lower data cluster) rise slowly over the generated voltage pulses, level off at approximately 180 pulses, and then remain substantially flat or constant. In each case, the average voltage of the 4.0 mm test apparatus is greater than that of the 2.5 mm test apparatus.

[0120] Figure 8 shows a comparison between the test IVL apparatus and a known IVL apparatus, and a subset of the data from Figure 7, namely comparing the peak pressure output generated by the first 80 voltage pulses for each apparatus type. Here, the voltage pulse (or number of pulses) is compared to the peak pressure generated during each voltage pulse. The known data, where the voltage in each voltage pulse is constant, exhibits a relatively significant decrease in pressure output as the voltage pulse progresses over time (dashed line). In contrast, the test data obtained using the voltage and pulse generation algorithms of Figure 2 (solid line) exhibits a pressure output line that decreases at a much smaller angle or slope. Thus, the pressure output of the test IVL apparatus provides a more stable or constant pressure output than that of the known IVL apparatus. The known IVL apparatus has a significant attenuation of pressure output as the voltage pulse progresses. More specifically, the test IVL apparatus results in a pressure output drop of less than 0.25 MPa over 80 pulses.

[0121] The tested pressure output was measured in vitro using a pressure sensor (hydrophone) placed outside the catheter balloon in an acoustic field generated by the device pulse delivery. The device and hydrophone under test were immersed in degassed and deionized water maintained at approximately body temperature.

[0122] This concept is further illustrated in Figure 9, where the average pressure generated by 80 pulses of a known IVL device (2.5 mm and 4.0 mm) with a constant voltage magnitude is compared to the average pressure generated by a test IVL device (2.5 mm and 4.0 mm) according to the voltage pulse and control method shown in Figure 2.

[0123] As shown in Figure 9, both the known 2.5 mm and 4.0 mm devices result in a pressure output slope that drops significantly as the voltage pulses progress up to 80 pulses. In contrast, the tested 2.5 mm and 4.0 mm devices result in a relatively flat, constant, or stable pressure output slope as the voltage pulses progress up to 300 pulses. Furthermore, the slope of the test pressure output line appears to increase slightly as the voltage pulses progress, which may be beneficial for fracturing difficult calcified areas. Here again, the known IVL devices have a significant and substantial pressure output attenuation beyond 80 pulses, showing a decrease of approximately 60% in pressure output. A significant decrease in pressure output beyond 80 pulses may include a decrease of more than 10% in pressure output, as the therapeutic effect is considerably (more than 10%) reduced. The test IVL devices show no pressure attenuation over 300 voltage pulses.

[0124] In summary, an IVL device operated and controlled in accordance with this disclosure provides voltage pulses with increasing voltage until an upper voltage magnitude threshold is reached. The voltage pulses may then proceed at the upper voltage magnitude threshold until 300 or more voltage pulses (a predetermined maximum number of voltage pulses) have been performed, or until the physician determines that treatment is complete, if the maximum number of voltage pulses has not been reached. This, as shown above, in certain embodiments, leads to a constant and / or slightly increasing pressure output from each voltage pulse. In some embodiments, the magnitude of the pressure output and the associated slope may be manipulated by changing the magnitude of each progressive increase in voltage. In some embodiments, the voltage magnitude may be progressively increased as shown in Figure 2. In other embodiments, the voltage magnitude may be progressively increased over at least two consecutive voltage pulses, then held constant over one or more voltage pulses, after which a subsequent sequence of voltage pulses may resume the progressive increase in magnitude. In other embodiments, the voltage magnitude may be decreased over one or more consecutive voltage pulses. All combinations of increasing, decreasing, and / or keeping the voltage unchanged over multiple sequences of voltage pulses to manipulate the resulting pressure output are within the scope of the present invention.

[0125] In addition, referring to the above disclosure, various embodiments of this disclosure can provide substantially the same pressure output for all balloon sizes, and the balloon sizes may be in the range of 2 mm to 4 mm in outer diameter. In these embodiments, larger balloon sizes are not necessarily required to have a lower pressure output than relatively smaller balloon sizes.

[0126] The data in Figures 8 and 9 also show that an IVL device operating according to this disclosure is capable of stable operation and pressure output over a predetermined maximum number of voltage pulses, including at least 300 voltage pulses. This is in contrast to the significant pressure attenuation of known IVL devices at just 80 voltage pulses.

[0127] Furthermore, the data in Figures 8 and 9 confirm that the IVL control system 22 shown in Figure 1 is controllable so that the pressure output following an electric arc event between two spaced electrodes can be controlled within upper and lower pressure magnitude thresholds or a pressure magnitude window. Moreover, the pressure output can be controlled using embodiments of the present disclosure in patterns of increasing pressure over treatment, decreasing pressure over treatment, constant pressure over treatment, and any combination thereof.

[0128] Examples of suitable processors may include, among other things, one or more microprocessors, integrated circuits, and system-on-a-chip (SoCs). Examples of suitable memory may include, among other things, one or more main memory and / or non-main memory (e.g., secondary, tertiary, etc.); permanent, semi-permanent, and / or temporary memory; and / or, but not limited to, memory storage devices including hard drives (e.g., magnetic, solid state), optical disks (e.g., CD-ROM, DVD-ROM), RAM (e.g., DRAM, SRAM, DRDRAM), ROM (e.g., PROM, EPROM, EEPROM, flash EEPROM), and volatile and / or non-volatile memory. The communication circuit 58 includes components to facilitate the operation of the processor, and for example, suitable components may include transmitters, receivers, modulators, demodulators, filters, modems, analog-to-digital (AD or DA) converters, diodes, switches, operational amplifiers, and / or integrated circuits. In some embodiments, memory 26 may represent one or more memory devices capable of operating for IVL therapeutic operations. For example, each memory (e.g., 154, 178) may be included as part of memory 26, shared with it, or separate from it.

[0129] In this disclosure, the consideration of a set of discharge electrodes is described in the context of a pair of electrodes, but in certain cases one of them may function as a cathode and the other as an anode. However, the number of electrodes in a set may be greater than one pair, and may include, for example, one or more cathodes in contact with one or more anodes. In addition, the apparatus, systems, and methods in this disclosure may include two or more groups of connected electrodes, which may be arranged electrically in series, in parallel, or independently of each other.

[0130] Figure 10 provides an illustrative flowchart showing an exemplary method 400 of one embodiment of the present invention. Thus, step 402 provides determining the outer diameter, or OD, of the balloon of the IVL device in question. This may be done by manual input to the IVL control system described above. Alternatively, the OD of the balloon may be automatically detected and determined by connecting the catheter to the IVL control system. Step 404 provides establishing an acceptable voltage pulse window, which has predetermined lower and upper voltage magnitude thresholds, which may also be stored in the IVL control system as described above. Step 406 provides performing a sequence of voltage pulses controlled and generated by the IVL control system at a predetermined lower voltage magnitude threshold, for which 10 pulses may be used in the example for explanation. Step 408 provides that if the IVL control system determines that the last sequence of voltage pulses performed did not meet the predetermined upper voltage threshold target, the IVL control system may instruct the execution and generation of another sequence of voltage pulses. Step 410 attempts to determine whether a predetermined maximum number of 300 voltage pulses, as illustrated, have been performed during the treatment, provided that the last sequence of voltage pulses performed has met a predetermined upper voltage threshold target. If Step 412 determines that 300 voltage pulses have been performed, the IVL control system terminates the treatment and does not allow any further voltage pulse generation. If 300 voltage pulses have not been performed, the IVL control system instructs the system to perform another sequence of voltage pulses at a predetermined upper voltage threshold target magnitude.

[0131] In certain embodiments, the apparatus, systems, and methods described herein may include voltage pulse frequencies of 1 pulse / second, 2 pulses / second, and / or 3 pulses / second. In some embodiments, the frequency or pulses / second generated by the described embodiments may be in the range of 1 to 5 pulses / second.

[0132] Moving on to Figure 11, and continuing to refer to Figures 1 to 10, some embodiments may include an IVL treatment flow 500 based on control data, which includes: a predetermined starting voltage; an upper voltage threshold; the width or duration of the voltage pulses to be generated and / or applied; a predetermined pause between consecutive adjacent voltage pulses; the number of generated voltage pulses required before the voltage is increased for the subsequent voltage pulse; the magnitude of the voltage increase for the subsequent voltage pulse; the time gap between adjacent voltage pulses in a sequence of voltage pulses; and the maximum number of voltage pulses. As described above, the control data may be stored in and executed by the control system 22. Alternatively, as also described above, the control data may be stored in memory, a processor, or an EPROM, and the control system 22 uses the control data to perform the treatment.

[0133] A viable IVL treatment flow 500 may be initiated in step 502 by generating an initiation voltage pulse and a predetermined duration or width of a voltage pulse of control data. A predetermined number of voltage pulses (a sequence of voltage pulses) provided by the control data may be performed in step 504, accompanied by a forced or mandatory pause of a predetermined duration before performing subsequent or adjacent sequences of voltage pulses.

[0134] Next, in step 506, the number of generated voltage pulses is monitored or determined and compared with the maximum allowable number of voltage pulses in the control data.

[0135] As in step 508, if the maximum number of voltage pulses has been generated, the control system 22 does not allow the generation of any further voltage pulses. In some embodiments, the generation of additional voltage pulses may be permitted by replacing the original catheter assembly 14 with a new catheter assembly, in which case the number of generated voltage pulses restarts from zero.

[0136] If the maximum number of voltage pulses to be generated has not been reached, step 510 provides the required pause between subsequent or adjacent sequences (or cycles) of the generated voltage pulses. The control data includes a predetermined length or duration of the required pause between adjacent sequences of voltage pulses.

[0137] Following the forced pause in step 510, step 512 determines whether the total number of generated voltage pulses satisfies the requirements of the control data for increasing the voltage magnitude of subsequent voltage pulses.

[0138] If the number of generated voltage pulses is insufficient to guarantee an increase in voltage magnitude, the operation flow returns to step 504 and subsequent steps described above.

[0139] As in step 514, if the number of generated voltage pulses is sufficient to guarantee an increase in voltage magnitude, the voltage magnitude is increased by a predetermined amount with respect to the subsequent voltage pulse. From step 514, the operation flow returns to step 504 and subsequent steps described above.

[0140] The apparatus, systems, and methods described herein, as well as related applications, are for illustrative purposes only and are not intended to limit the scope of the invention. Features of various embodiments may be combined with other embodiments within the intent of the invention. Modifications and alterations of the embodiments disclosed herein are possible, and practical substitutes and equivalents of various elements of the embodiments will be understood by those skilled in the art when considering this patent document. These and other modifications and alterations of the embodiments disclosed herein may be made without departing from the scope and spirit of the invention. [Explanation of Symbols]

[0141] 12 IVL System 18 electrodes 22 IVL control system 24 processors 26 memory 28 circuits 112 Energy Storage Systems 114 Capacitors, energy storage elements 116 Relay System 120 Charging Control System 122 Conversion System 124 Step-Down Regulator System 130 Discharge Switch System 131 Driver 132 Semiconductor equipment, gate switches 134 diodes 138 Flow divider 140 Power Monitoring System 142 Current Monitoring System 144 Amplifier 146 Conditioning Network 148 Buffer amplifier 150 ADC System 152 Converters 154 memory 170 Voltage Monitoring System 172 Resistor Network 174 Operational Amplifier Network 176 ADC Conversion System 178 FIFO memory 180 Energy Storage Capacity Voltage Monitoring System 182 Amplifier Configuration 184 Amplifier 186 Comparator 188 Resistor-Resistor-Capacitor Network 190 Umbrella Surveillance System 192 Flip-flops 194 Logic Gates 200 Voltage pulse generation and control system

Claims

1. An intravascular lithotripsy ("IVL") catheter assembly, At least one set of electrodes for placement within a body lumen while housed in an inflatable balloon or enclosure, The present invention comprises an electrical pulse generation system for supplying electrical energy to the at least one set of spaced electrodes to generate a spark for IVL treatment, wherein the electrical pulse generation system includes an IVL control system, the IVL control system comprises a processor for executing instructions at least partially based on a set of stored control data, and a circuit configuration adapted for signal communication based on the operation of the processor, and the IVL control system A predetermined number of voltage pulses are generated and applied to the at least one pair of spaced electrodes, wherein the magnitude of each voltage pulse in the initial sequence of voltage pulses includes a target voltage set to a predetermined lower voltage magnitude threshold. After the initial continuous generation of the voltage pulse, a pause of a predetermined duration is required. A predetermined number of voltage pulses are generated in succession and applied to the at least one pair of spaced electrodes. Determine when the number of generated voltage pulses is sufficient to guarantee an increase in the magnitude of subsequent voltage pulses, and based on such determination, increase the magnitude of the subsequent voltage pulses by a predetermined amount. Generate another sequence of a predetermined number of voltage pulses and apply them to the at least one set of spaced electrodes. It is configured in such a way, An IVL catheter assembly wherein at least a portion of the generated voltage pulse generates an electric arc between the separated electrodes of the at least one set of separated electrodes, and each electric arc generates a pressure output.

2. The IVL catheter assembly according to claim 1, wherein the predetermined lower voltage magnitude threshold is approximately 2850 volts.

3. The IVL catheter assembly according to any one or both of claims 1 and 2, wherein the IVL control system is further configured to determine the point in time when a predetermined upper limit threshold voltage magnitude is reached.

4. The IVL catheter assembly according to claim 3, further configured so as to stop increasing the voltage magnitude when the IVL control system determines that the voltage magnitude has reached a predetermined upper limit threshold voltage magnitude.

5. The IVL catheter assembly according to claim 3, wherein the predetermined upper limit threshold voltage magnitude is approximately 3250 volts.

6. The IVL catheter assembly according to any one or more of claims 1 to 5, wherein the duration of the pause is between approximately 5 seconds and approximately 20 seconds.

7. The IVL catheter assembly according to any one or more of claims 1 to 5, wherein the duration of the pause is approximately 10 seconds.

8. The IVL catheter assembly according to any one or more of claims 1 to 7, further comprising a predetermined duration for applying the voltage to at least one set of electrodes.

9. The IVL catheter assembly according to claim 8, wherein the duration or width of the application of the voltage is in the range of about 20 microseconds to about 30 microseconds.

10. The IVL catheter assembly according to claim 8, wherein the duration or width of the application of the voltage is approximately 25 microseconds.

11. The IVL catheter assembly according to any one or more of claims 1 to 10, wherein the IVL control system is further configured to increase the magnitude of the subsequent voltage pulses by a predetermined amount of approximately 25 volts if the IVL control system determines that the number of generated voltage pulses is sufficient to ensure an increase in the magnitude of the subsequent voltage pulses.

12. The IVL catheter assembly according to any one or more of claims 1 to 11, wherein the IVL control system further includes a predetermined maximum number of voltage pulses of the IVL catheter assembly that are in the range of 10 to 300 voltage pulses, and the IVL control system is configured to prevent the execution of further voltage pulses when it determines that the predetermined maximum number of voltage pulses has been generated.

13. The IVL catheter assembly according to any one or more of claims 1 to 12, wherein the electric arc generates a pressure output that does not attenuate or decrease by more than 0.25 MPa on average over a predetermined maximum number of voltage pulses.

14. The IVL catheter assembly according to any one or more of claims 1 to 12, wherein the electric arc generates a pressure output that does not decrease by more than 10% over a predetermined maximum number of voltage pulses.

15. The IVL catheter assembly according to any one or more of claims 1 to 12, wherein the pressure output of the last voltage pulse among the predetermined maximum number of voltage pulses is greater than the pressure output of the first voltage pulse.

16. The IVL catheter assembly according to claim 15, wherein the electric arc generates a pressure output over time, the pressure output includes a gradient of the pressure output of the generated voltage pulses over time, and the gradient increases over time.

17. The IVL catheter assembly according to any one of claims 1 to 14, wherein the electric arc generates a pressure output over time, the pressure output includes a gradient of the pressure output of the generated voltage pulses over time, and the gradient decreases over time.

18. An intravascular fragmentation system according to any one or more of claims 1 to 12, wherein the electric arc generates a pressure output, the pressure output includes a gradient of the pressure output of the generated voltage pulse, and the gradient of the pressure output of the voltage pulse exhibits a substantially constant pressure magnitude output over the voltage pulse.

19. The intravascular fragmentation system according to any one or more of claims 1 to 18, further comprising a plurality of the generated sequences of the predetermined number of voltage pulses.

20. The IVL catheter assembly according to claim 19, wherein one or more of the sequences of generated voltage pulses in the plurality of generated voltage pulses comprises 10 voltage pulses.

21. The IVL catheter assembly according to claim 20, wherein in the plurality of sequences of generated pulses, one or more of the sequences of generated voltage pulses comprises more than 10 voltage pulses.

22. The IVL catheter assembly according to claim 19, wherein one or more of the sequences of generated voltage pulses in the plurality of sequences of generated voltage pulses include fewer than 10 voltage pulses.

23. The IVL catheter assembly according to any one or more of claims 1 to 22, wherein the stored control data includes a predetermined lower voltage magnitude threshold, a predetermined duration of the application of the generated voltage pulses to the at least one pair of electrodes, and a predetermined duration of the pause.

24. The IVL catheter assembly according to any one or more of claims 1 to 23, wherein the stored control data further includes one or more of a maximum upper limit voltage threshold, a predetermined duration between adjacent voltage pulses in a sequence of voltage pulses, a predetermined number of voltage pulses required before an increase in voltage magnitude is guaranteed, and at least one predetermined magnitude for increasing the voltage.

25. The IVL catheter assembly according to any one or more of claims 1 to 24, wherein the stored control data further includes the maximum number of voltage pulses allowed for the IVL catheter assembly.

26. The IVL catheter assembly according to any one or more of claims 1 to 25, wherein the stored control data further includes a current threshold.

27. The IVL catheter assembly according to any one or more of claims 1 to 26, further comprising an EPROM configured to store the stored control data.

28. An intravascular lithotripsy ("IVL") catheter assembly, At least one set of electrodes for placement within a body lumen while housed in an inflatable balloon or enclosure, The present invention comprises an electrical pulse generation system for supplying electrical energy to the at least one set of electrodes and generating sparks for IVL treatment, wherein the electrical pulse generation system includes a current monitoring system and an IVL control system, and the IVL control system comprises a processor for executing instructions at least partially based on a set of stored control data and a circuit configuration adapted for signal communication based on the operation of the processor. The current monitoring system is configured to determine the current flow generated by the voltage pulse, The IVL control system, In response to an initial voltage magnitude setting including a predetermined magnitude of the voltage pulse and an initial duration setting including a predetermined duration for applying the voltage pulse to the spaced electrodes, a voltage pulse is generated to be applied to the at least one pair of electrodes. The determined current flow is compared with a predetermined current threshold, This determines whether the initial voltage magnitude setting and the initial duration setting were sufficient to generate an electric arc between the separated electrodes. An IVL catheter assembly configured as follows.

29. The IVL catheter assembly according to claim 28, wherein the IVL control system is further configured to increase the initial voltage magnitude setting by a predetermined amount if the IVL control system determines that the initial voltage magnitude setting and the initial duration setting are not sufficient to generate an electric arc.

30. The IVL catheter according to any one or both of claims 28 and 29, wherein the IVL control system is further configured to increase the initial duration setting by a predetermined amount if the IVL control system determines that the voltage magnitude setting and the initial duration setting are not sufficient to generate an electric arc.

31. The IVL catheter according to claim 28, wherein the IVL control system is further configured to increase the initial voltage magnitude setting and the initial duration setting by a predetermined amount if the IVL control system determines that the initial voltage magnitude and duration setting are not sufficient to generate an electric arc.

32. The IVL catheter assembly according to claim 28, wherein the IVL control system is configured to generate a next voltage pulse to be applied to the at least one set of electrodes with the initial voltage magnitude and initial duration setting when it determines that the initial voltage magnitude and initial duration setting have generated an electric arc, and the IVL control system is configured to determine whether the next voltage pulse has generated an electric arc.

33. An intravascular lithotripsy ("IVL") catheter assembly, At least one set of electrodes for placement within a body lumen while housed in an inflatable balloon or enclosure, The present invention comprises an electrical pulse generation system for supplying electrical energy to the at least one set of electrodes and generating sparks for IVL treatment, wherein the electrical pulse generation system includes a current monitoring system and an IVL control system, and the IVL control system comprises a processor for executing instructions at least partially based on a set of stored control data and a circuit configuration adapted for signal communication based on the operation of the processor. The current monitoring system is configured to determine the current flow generated by each of the voltage pulses in a sequence of voltage pulses. The IVL control system, In response to an initial voltage magnitude setting including a predetermined magnitude of the voltage pulse and an initial duration setting including a predetermined duration of the initial continuous application of the voltage pulse to the spaced electrodes, the initial continuous application of the voltage pulse is generated for application to the at least one pair of electrodes. In the initial sequence of voltage pulses, the average current flow is calculated from the determined current generated by each of the voltage pulses. The calculated average current is compared with a predetermined current threshold, Before the start of a subsequent sequence of voltage pulses, it is determined whether the initial voltage magnitude setting and the initial duration setting were sufficient to generate an electric arc for each voltage pulse in the initial sequence of voltage pulses. An IVL catheter assembly configured as follows.

34. The IVL catheter assembly according to claim 33, wherein the IVL control system is further configured to increase the initial voltage magnitude setting by a predetermined amount if the IVL control system determines that the initial voltage magnitude setting and the initial duration setting are not sufficient to generate an electric arc with respect to each voltage pulse in the initial sequence of voltage pulses before the start of a subsequent sequence of voltage pulses.

35. An IVL catheter according to any one or both of claims 33 and 34, wherein the IVL control system is further configured to increase the initial duration setting by a predetermined amount if the IVL control system determines that the initial voltage magnitude setting and the initial duration setting are not sufficient to generate an electric arc with respect to each voltage pulse in the initial sequence of voltage pulses before the start of a subsequent sequence of voltage pulses.

36. An IVL catheter according to any one or more of claims 33 to 35, wherein the IVL control system is further configured to increase the initial voltage magnitude setting and the initial duration setting by a predetermined amount if the IVL control system determines that the initial voltage magnitude and duration setting is not sufficient to generate an electric arc with respect to each voltage pulse in the first sequence of voltage pulses before the start of a subsequent sequence of voltage pulses.

37. The IVL catheter assembly according to any one or more of claims 33 to 36, wherein the IVL control system is configured to generate a succession of voltage pulses and apply them to the at least one set of electrodes when the IVL control system determines that the initial voltage magnitude and initial duration settings are sufficient to generate an electric arc.

38. The IVL control system, From the determined current flow generated by each of the voltage pulses in the subsequent sequence of voltage pulses, the subsequent average current flow is calculated. The subsequent average current flow calculated above is compared with the predetermined current threshold, Determining whether the initial voltage magnitude and duration settings were sufficient to generate an electric arc with respect to each voltage pulse in the subsequent sequence of voltage pulses. The IVL catheter according to claim 37, further configured as follows.

39. The IVL catheter according to any one or more of claims 33 to 38, wherein the IVL control system is further configured to require a pause of a predetermined duration after the initial sequence of generated voltage pulses and before the generation of the subsequent sequence of voltage pulses begins.

40. An intravascular lithotripsy ("IVL") catheter assembly, At least one set of electrodes for placement within a body lumen while housed in an inflatable balloon or enclosure, The present invention comprises an electrical pulse generation system for supplying electrical energy to the at least one set of spaced electrodes to generate a spark for IVL treatment, wherein the electrical pulse generation system includes an IVL control system, the IVL control system comprises a processor for executing instructions at least partially based on a set of stored control data, and a circuit configuration adapted for signal communication based on the operation of the processor, and the IVL control system It is configured to generate a predetermined number of voltage pulses to be applied to at least one set of spaced electrodes, At least some of the generated voltage pulses create an electric arc between the separated electrodes of the at least one set of separated electrodes, An IVL catheter assembly in which each electric arc generates a pressure output that does not decrease by more than 10% over the generated voltage pulse.

41. A method for performing intravascular pulverization ("IVL"), To prepare a catheter assembly, the catheter assembly is At least one set of electrodes for placement within a body lumen while housed in an inflatable balloon or enclosure, To provide an electrical pulse generation system for supplying electrical energy to the at least one set of electrodes and generating a spark for IVL treatment, wherein the electrical pulse generation system includes an IVL control system, the IVL control system comprising a processor for executing instructions at least partially based on a set of stored control data, and a circuit configuration adapted for signal communication based on the operation of the processor, Generating an initial sequence of a predetermined number of voltage pulses to be applied to at least one set of electrodes, wherein the magnitude of each voltage pulse in the initial sequence of voltage pulses includes a target voltage set to a predetermined lower voltage magnitude threshold, and a pause of a predetermined duration is required after the generation of the initial sequence of voltage pulses. To generate a predetermined number of consecutive voltage pulses and apply them to the at least one set of electrodes, Determine when the number of generated voltage pulses is sufficient to guarantee an increase in the magnitude of subsequent voltage pulses, and based on such determination, increase the magnitude of the subsequent voltage pulses by a predetermined amount. To generate another sequence of a predetermined number of voltage pulses in at least one set of electrodes. Methods that include...

42. A method for performing intravascular pulverization ("IVL"), To prepare a catheter assembly, the catheter assembly is At least one set of electrodes for placement within a body lumen while housed in an inflatable balloon or enclosure, To provide an electrical pulse generation system for supplying electrical energy to the at least one set of electrodes and generating sparks for IVL treatment, wherein the electrical pulse generation system includes a current monitoring system and an IVL control system, and the IVL control system includes a processor for executing instructions at least partially based on a set of stored control data and a circuit configuration adapted for signal communication based on the operation of the processor, Determining the current flow generated by each of the voltage pulses in the aforementioned sequence of voltage pulses, In response to an initial voltage magnitude setting including a predetermined magnitude of the voltage pulse and an initial duration setting including a predetermined duration of the initial continuous application of the voltage pulse to the spaced electrodes, the initial continuous application of the voltage pulse is generated for application to the at least one pair of electrodes. Calculating the average current flow from the determined current flow generated by each of the voltage pulses in the aforementioned sequence of voltage pulses, The calculated average current flow is compared with a predetermined current threshold, Before initiating a subsequent sequence of voltage pulses, determine whether the initial voltage magnitude and duration settings were sufficient to generate an electric arc for each voltage pulse in the initial sequence of voltage pulses. Methods that include...

43. A method for performing intravascular pulverization ("IVL"), To prepare a catheter assembly, the catheter assembly is At least one set of electrodes for placement within a body lumen while housed in an inflatable balloon or enclosure, To provide an electrical pulse generation system for supplying electrical energy to the at least one set of electrodes and generating sparks for IVL treatment, wherein the electrical pulse generation system includes a current monitoring system and an IVL control system, and the IVL control system includes a processor for executing instructions at least partially based on a set of stored control data and a circuit configuration adapted for signal communication based on the operation of the processor, Determining the current flow generated by each of the voltage pulses in the aforementioned sequence of voltage pulses, In response to an initial voltage magnitude setting including a predetermined magnitude of the voltage pulse and an initial duration setting including a predetermined duration of the initial continuous application of the voltage pulse to the spaced electrodes, the initial continuous application of the voltage pulse is generated for application to the at least one pair of electrodes. Calculating the average current flow from the determined current flow generated by each of the voltage pulses in the aforementioned sequence of voltage pulses, The calculated average current flow is compared with a predetermined current threshold, Before initiating a subsequent sequence of voltage pulses, determine whether the initial voltage magnitude and duration settings were sufficient to generate an electric arc for each voltage pulse in the initial sequence of voltage pulses. Methods that include...

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