A cyclic suction system that uses a dual pressure generator receptacle instead of a vacuum pump to generate a cyclic suction pressure waveform.

Abstract

A cyclic aspiration system generates a periodic aspiration pressure waveform that alternates between a vacuum pressure below atmospheric pressure and a positive pressure above vacuum pressure. The system includes a dual pressure generator receptacle disposed proximal to and connected in fluid communication with a suction catheter. The dual pressure generator receptacle receives a collectable fluid therein that can be subjected to intermittent and cyclic application or removal of a compressive force via a linear displacement mechanism. While the collectable fluid in the dual pressure generator receptacle is subjected to a compressive force, a positive pressure is generated, and when the collectable fluid is not subjected to a compressive force, a vacuum pressure is generated. The periodic aspiration pressure waveform is generated via the dual pressure generator receptacle without the use of a separate vacuum pump.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of U.S. Provisional Patent Application No. 63 / 447,506, filed February 22, 2023, the disclosure of which is incorporated herein by reference in its entirety.

[0002] FIELD OF THE INVENTION The present disclosure relates generally to systems and methods used during thrombectomy procedures for capturing and removing occlusions or thrombi. Specifically, the present disclosure relates to a cyclic aspiration system for capturing and removing occlusions or thrombi in a blood vessel, where the cyclic aspiration pressure waveform includes intermittent periodic intervals of vacuum pressure (i.e., below atmospheric pressure) and positive pressure (i.e., greater than vacuum pressure, and in some cases greater than atmospheric pressure). The cyclic aspiration system generates the cyclic aspiration waveform without the use of a vacuum pump (e.g., a centrifugal pump, a piston pump, or a diaphragm pump). In particular, the present disclosure is directed to a cyclic aspiration system and method in which a cyclic aspiration pressure waveform is generated using a dual pressure generator receptacle associated with an inlet tube or rotary hemostasis valve (RHV) positioned proximally of the aspiration catheter, and in which fluid collectable in the dual pressure generator receptacle can be intermittently and cyclically subjected to the application or removal of a compressive force via a linear displacement mechanism to generate both vacuum pressure intervals and positive pressure intervals of the cyclic aspiration pressure waveform without the use of a vacuum pump (e.g., a centrifugal pump, a piston pump, or a diaphragm pump). [Background technology]

[0003] Pulsatile or cyclic aspiration applies a cyclic pressure waveform with intermittent, cyclical minimum / low / vacuum / aspiration pressure and maximum / peak / high pressure. During the cycles under minimum / low / vacuum / aspiration pressure, the thrombus is drawn proximally and captured at the distal tip / end of the aspiration catheter, while during the cycles under maximum / peak / high pressure, the thrombus is pushed distally. When utilizing pulsatile or cyclic aspiration during thrombus capture and removal, it is desirable to maximize the cycling frequency of the cyclic pressure waveform, thus maximizing thrombus oscillation and thereby optimizing aspiration performance. One significant challenge in maximizing cycling frequency is the specific response time required for the mechanical actuation of each active component, which limits the range over which the cycling frequency can be increased. Complex conventional systems for maximizing cycling frequency have many active components, each of which must wait a response time before being activated to maintain normal operation. Therefore, in complex systems with many active components, the range over which the cycling frequency can be maximized is undesirably reduced. Another concern is the tendency of conventional aspiration systems to become clogged by trapped thrombus. Summary of the Invention [Problem to be solved by the invention]

[0004] It would therefore be desirable to develop an improved cyclic suction system that utilizes as few active components as possible, has the longest associated response time to achieve the highest cycling frequency, minimizes damping of positive pressure waves, and has the added benefit of reducing the overall cost of manufacture. It would further be desirable to develop an improved cyclic suction system that prevents or minimizes the risk of blockage. [Means for solving the problem]

[0005] One aspect of the present disclosure relates to a pulsatile or cyclic aspiration system that generates periodic aspiration pressure waveforms at intermittent, periodic intervals of subatmospheric vacuum pressure and positive pressure above vacuum pressure (higher than vacuum pressure, and in some cases higher than atmospheric pressure) using as few active components as possible, with the longest response time associated with achieving maximum cycling frequency, with the additional benefits of minimizing damping of positive pressure waves and reducing overall cost of manufacture.

[0006] Another aspect of the present disclosure is directed to a cyclic suction system for generating a cyclic suction pressure waveform without the use of a vacuum pump (e.g., a centrifugal pump, a piston pump, or a diaphragm pump).

[0007] Yet another aspect of the present disclosure relates to an improved cyclic suction system for generating a cyclic suction pressure waveform using dual pressure generator receptacles as a single device to generate intervals of both subatmospheric vacuum pressure and positive pressure above the vacuum pressure of the cyclic suction pressure waveform without the use of a vacuum pump (e.g., a centrifugal pump, a piston pump, or a diaphragm pump).

[0008] Yet another aspect of the present disclosure is directed to an improved cyclic aspiration system for generating a cyclic aspiration pressure waveform, wherein fluid (e.g., blood and / or saline) collectable in a dual pressure generator receptacle is subjected to application or removal of a compressive force.

[0009] Another aspect of the present disclosure relates to an improved cyclic aspiration system for generating a cyclic aspiration pressure waveform, in which a fluid (e.g., blood and / or saline) collectable in a dual pressure generator receptacle is associated with an inlet tube located proximal to the proximal hub of the aspiration catheter or within the vacuum inlet port of a rotary hemostasis valve.

[0010] Another aspect of the present disclosure is directed to an improved cyclic aspiration system for generating a cyclic aspiration pressure waveform in which components contaminated by blood (e.g., collection container, syringe / reservoir, plunger or piston, inlet tubing, connector, one-way valve, catheter hub / rotating hemostasis valve (RHV), and aspiration catheter) can be either separate or as an assembled unit / module that is discarded after a single use, while the linear displacement mechanism is not contaminated by blood and is therefore reusable. [Brief explanation of the drawings]

[0011] The above and further aspects of the present disclosure will be further discussed with reference to the following description in conjunction with the accompanying drawings, in which like numerals indicate like structural elements and features in the various drawings. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the present disclosure. The figures depict one or more implementations of the device by way of example only, and not by way of limitation. [Figure 1A] An example of a cyclic aspiration system according to the present disclosure that generates a cyclic aspiration pressure waveform, wherein the dual pressure generator receiver is a syringe connected in fluid communication with an inlet tube proximal to a proximal hub remote from the aspiration catheter, and collectable fluid within the syringe is compressible internally via a plunger or piston slidable within the barrel of the syringe. [Figure 1B] 1B illustrates the exemplary cyclic aspiration system of FIG. 1A prior to treatment while being prepared by flushing with saline prior to use in capturing a target thrombus. [Figure 1C] 1B illustrates the exemplary cyclic aspiration system of FIG. 1A during the generation of vacuum pressure intervals of the cyclic aspiration pressure waveform by retracting a plunger or piston within the barrel of a syringe to capture a thrombus at the distal tip / end of the aspiration catheter. [Figure 1D] 1A shows the exemplary cyclic aspiration system during generation of positive pressure intervals of the cyclic aspiration pressure waveform by advancing a plunger or piston within the barrel of a syringe while a thrombus resides at the distal tip / end of the aspiration catheter. [Figure 1E] FIG. 1A shows an exemplary cyclic aspiration system that includes a spring-loaded reciprocating mechanism for intermittently and cyclically displacing (i.e., retracting or advancing) a plunger or piston within a syringe barrel that generates a cyclic aspiration pressure waveform. [Figure 2A] FIG. 12 is a side view of another exemplary cyclic aspiration system according to the present disclosure for generating a cyclic aspiration pressure waveform, wherein the dual pressure generator receptacle is a vacuum inlet port of a rheostatic valve connected to an aspiration catheter, the volume within the vacuum inlet port being internally compressible via a reciprocating plunger or piston slidable therein, and the plunger or piston is shown in a retracted state during generation of a vacuum pressure interval of the cyclic aspiration pressure waveform. [Figure 2B] 2B is a side view of the exemplary cyclic aspiration system of FIG. 2A depicted during the generation of a positive pressure interval of the cyclic aspiration pressure waveform with the plunger or piston in an advanced state. [Figure 3A] FIG. 10 is a side view of yet another exemplary cyclical suction system according to the present disclosure for generating a cyclical suction pressure waveform in which the dual pressure generator receptacle is a bellows-shaped container that can transition from an axially expanded state to an axially collapsed state upon receiving an external axial force, shown during generation of a vacuum pressure interval of the cyclical suction pressure waveform in a default axially uncollapsed state (i.e., no external axial force). [Figure 3B] FIG. 3B is a side view of the exemplary cyclic suction system of FIG. 3A during the generation of a positive pressure interval of the cyclic suction pressure waveform, with the bellows container shown in an axially collapsed state (i.e., subjected to an external axial force). [Figure 4A] 1 is yet another exemplary cyclic aspiration system according to the present disclosure generating a cyclic aspiration pressure waveform in which the dual pressure generator receptacle is a liquid reservoir with fluid (e.g., blood and / or saline) collected therein that is compressible by a slidable plunger or piston therein, shown during a vacuum pressure interval of the cyclic aspiration pressure waveform with the plunger or piston in a retracted state within the liquid reservoir. [Figure 4B]4B illustrates the exemplary cyclic aspiration system of FIG. 4A during the generation of a positive pressure interval of the cyclic aspiration pressure waveform, with the plunger or piston in an advanced position within the liquid reservoir. DETAILED DESCRIPTION OF THE INVENTION

[0012] As used herein, the term "about" or "approximately" in connection with any numerical value or numerical range indicates a suitable dimensional tolerance that enables a portion of a component or a collection of components to function for its intended purpose as described herein. More specifically, "about" or "approximately" may refer to a range of values ​​of ±20% of the recited value; for example, "about 90%" may refer to a range of values ​​of 71% to 99%.

[0013] As used herein, the terms "tubular" and "tube" are intended to be broadly construed and are not limited to right cylindrical structures, or structures that are strictly circular in cross section, or structures that are uniform in cross section throughout their length. For example, a tubular structure or tubular system is generally depicted as a substantially right cylindrical structure. However, a tubular system can have a tapered or curved outer surface without departing from the scope of the present disclosure.

[0014] The documents incorporated by reference into this patent application should be considered an integral part of this application, provided that to the extent that any term is defined in these incorporated documents in a manner that contradicts the definition given herein, either expressly or implicitly, only the definition given herein should be considered.

[0015] A cyclic aspiration system according to the present disclosure generates a cyclic aspiration pressure waveform with intermittent, periodic intervals of vacuum pressure (i.e., pressure below atmospheric pressure) and positive pressure (i.e., pressure above vacuum pressure) without using a vacuum pump (e.g., a centrifugal pump, a piston pump, or a diaphragm pump). Instead, a cyclic aspiration system according to the present disclosure generates the cyclic aspiration waveform using a dual pressure generator receptacle associated with either the proximal inlet tube of the aspiration catheter or the rotary hemostasis valve. Collected fluid (e.g., blood and / or saline) within the dual pressure generator receptacle is subjected to the application or removal of a compressive force in an intermittent, periodic manner, generating both the vacuum pressure and the positive pressure intervals of the cyclic aspiration pressure waveform.

[0016] Several non-limiting examples of dual pressure generators capable of generating periodic suction pressure waveforms within a cyclic suction system without the use of a vacuum pump (e.g., a centrifugal pump, a piston pump, or a diaphragm pump) in accordance with the present disclosure are shown and described herein.

[0017] 1A shows an exemplary cyclic aspiration system without a vacuum pump according to the present disclosure, in which the dual pressure generator receptacle is a syringe associated with an inlet tube disposed proximal to a proximal hub attached to the aspiration catheter. A syringe 105 having a displaceable plunger or piston 115 slidable within the syringe barrel is connected via a three-way (e.g., T-shaped) connector 125 in fluid communication with the inlet tube 120 and the proximal hub 103 attached to (or an integral part of) the aspiration catheter 100. A one-way valve 130' is disposed proximal to the proximal hub 103. Retraction of the plunger 115 within the syringe generates vacuum pressure, opening the one-way valve 130' and allowing fluid from the aspiration catheter 100 to be drawn or aspirated therethrough. As the plunger 115 advances within the syringe 105, the positive pressure pushing against both the collection container 140 and the aspiration catheter 100 closes the one-way valve 130', preventing fluid from being injected into the aspiration catheter and preventing the clot from being pushed too far forward.

[0018] The proximal end of the inlet tube 120 in the illustrated example is Y-split into two respective inlet ports, including first inlet port 120a' and second inlet port 120a'' (shown exaggerated in FIG. 1A). It is also contemplated and within the scope of the present disclosure that the proximal end of the inlet tube 120 is a single tube with dual lumens arranged either concentrically or eccentrically. A flow restrictor 135 is associated with the first inlet port 120a', and a one-way valve 130 is associated with the second inlet port 120a''. Both inlet ports 120a, 120a'' empty into a collection container 140, preferably a disposable bag, for collecting fluid (e.g., saline during priming / cleaning before use, and / or blood during use). Prior to use, the cyclic aspiration system may be primed or cleaned to eliminate air from the system by aspirating a relatively small amount of saline (or blood) from the system via a syringe 105, as shown in FIG. 1B. To ensure the system is air-free, the distal end of inlet tube 120, connected to the proximal end of the aspiration catheter, is immersed in a dish of saline and plunger 115 is retracted, aspirating or drawing saline or blood into syringe 105. Plunger 115 is then advanced within syringe 105, pushing the saline or blood along inlet tube 120 toward collection container 140. To maximize the total volumetric capacity of collection container 140 during aspiration, preferably during priming or rinsing, the collection container is filled with no more than 5% saline.

[0019] The generation of vacuum pressure intervals of the periodic aspiration pressure waveform is shown in FIG. 1C with the retraction or pullback (as indicated by the directional arrows) of the plunger or piston 115 within the barrel of the syringe 105 creating vacuum pressure within the syringe 105. Vacuum pressure, albeit unevenly, is drawn between the aspiration catheter 100 and the collection reservoir 140. That is, contraction of the inlet tube 120 draws a minimal amount (e.g., ≦about 5%) of fluid from the collection reservoir 140 (as indicated by the thin directional arrow pointing distally) through the first inlet port 120a′, resulting in negligible, insignificant, or slight loss or reduction of suction from the distal tip of the aspiration catheter 100. The remaining suction (e.g., ≧about 95%) (as indicated by the thick directional arrow pointing proximally) is drawn from the distal tip / end of the aspiration catheter 100, drawing the thrombus 165 therein.

[0020] The generation of positive pressure intervals of the periodic aspiration pressure waveform is shown in FIG. 1D with a clot 165 lodged at the distal tip / end of the aspiration catheter 100. Positive pressure is generated by advancing the plunger or piston 115 within the barrel of the syringe 105 (as indicated by the directional arrows), forcing positive pressure, albeit unevenly, into the aspiration catheter 100 and collection reservoir 140. Specifically, a minimal amount (e.g., ≦about 5%) of forced positive pressure (as indicated by the thin directional arrow pointing proximally) enters the collection reservoir 140 via the first inlet port 120a′, resulting in negligible, insignificant, or insignificant loss or reduction of the forced positive pressure applied to the distal tip of the aspiration catheter. The remaining forced positive pressure (e.g., ≧about 95%) (as indicated by the thick directional arrow pointing distally) is applied to the distal tip / end of the aspiration catheter 100, expelling the clot 165. When the positive pressure within the second inlet port 120a″ exceeds a predetermined set pressure (e.g., 10,000 Pa), the one-way valve 130 (i.e., one-way) opens. Selecting a one-way valve with a relatively low predetermined set pressure allows aspirated blood within the system to enter the collection container 140 at a relatively low pressure when a blood clot is not lodged at the distal tip / end of the aspiration catheter. Even when the one-way valve 130 opens at the predetermined set pressure (e.g., 10,000 Pa), the positive pressure within the cyclic aspiration system may reach a significantly higher pressure through the one-way valve 130 that exceeds the base flow limit (e.g., when a blood clot is lodged at the distal tip / end of the aspiration catheter, as depicted in FIG. 1D ). If the syringe 105 is applying a flow rate that exceeds the base flow rate that the one-way valve can dissipate, the positive pressure within the cyclic aspiration system will build up or increase within the second inlet port 120a″ (as indicated by the thicker directional arrow pointing proximally in FIG. 1D ).

[0021] FIG. 1E shows a reciprocating plunger or piston 115 that is cyclically retracted or advanced by a spring-loaded rotating wheel 150 (i.e., a linear displacement mechanism). Different sizes or volumes of collection containers 140 (e.g., disposable collection bags (e.g., low, medium, and high)) can be sold separately or together to collect low, medium, and high volumes of aspirated fluid (e.g., blood and / or saline). Furthermore, multiple systems such as those shown in FIG. 1A can be connected together in series to accommodate larger volumes of aspirated fluid. This simplified system advantageously uses only syringes, with which physicians and interventionists have a known familiarity with their use. Preferably, the overall cost of manufacturing this simplified system is inexpensive enough that the components (e.g., collection container, syringe, plunger or piston, inlet tubing, connector, catheter hub, and aspiration catheter) can be sold either separately or as an assembled unit / module that is discarded or disposed of after a single use. A relatively large-capacity syringe, e.g., a 60 mL syringe, is preferably used without needing to be replaced. One or more non-disposable, reusable electronic components, such as a pressure sensor, variable restrictor, wireless dongle, battery, and motor, may be used with the system separately from the disposable component module, which is contaminated by blood, without being contaminated by blood. When a motor is not used, other non-disposable electronic components in the cyclic aspiration system operate using less power or energy. The example in FIG. 1E shows a cyclic aspiration system having an aspiration catheter 100 connected to a rotating hemostatic valve 103 (instead of the proximal hub 103 shown in FIGS. 1A-1D). A thrombus capture device (e.g., a stentriever) may also be positioned within the inlet tube 120 to assist in the removal of aspirated thrombus therein.

[0022] Instead of a piston or plunger displaceable within the barrel of a syringe associated with the inlet tube, in an alternative cyclic aspiration system according to the present disclosure, the plunger or piston may be displaceable within a port of a rotary hemostatic valve (RHV), as shown in FIGS. 2A and 2B . A reciprocating plunger or piston 215, shown in a retracted state, is displaceable within a pressure port 205 of the rotary hemostatic valve, which may optionally include a main port 203 for receiving an auxiliary device (e.g., a stentriever) therethrough. The plunger or piston 215 is preferably spring-loaded 217 so as to return to its natural or default retracted state when not subjected to an external force. The plunger 215 is reciprocally actuated (i.e., advanced within the pressure port 205 of the RHV) when intermittently engaged with an actuation wheel 250 (i.e., a linear displacement mechanism). In FIG. 2A , rotation of the actuation wheel 250 is achieved using a manually powered spur gear arrangement. Specifically, actuation wheel 250 is attached to a first gear (i.e., pinion) 260, which is driven by a second gear (i.e., wheel) 262, which is manually powered via a circular spiral spring. Activation or release of the spiral spring powers wheel 262, which drives pinion 260, thereby rotating actuation wheel 250, which is attached to the pinion. The spiral spring allows for continuous operation of the cyclic suction system at a constant speed for a predetermined period of time, e.g., approximately two minutes. During operation, during continuous rotation, actuation wheel 250 intermittently and periodically disengages and engages plunger 215. During disengagement (i.e., no external force is applied by actuation wheel 250), spring-loaded plunger 215 automatically returns to its natural or default retracted state, creating vacuum pressure within the RHV. Meanwhile, during engagement (i.e., application of an external force), the plunger 215 advances distally within the RHV's pressure port 205, compressing the aspirated fluid collected therein and creating a positive pressure. While under vacuum pressure, the aspirated fluid within the system may be collected or stored in a collection container 240, preferably a disposable bag, connected to a side port 205a of the RHV's pressure port 205.Disposed within side port 205a is a first backflow prevention device 230 (e.g., a duckbill valve, one-way valve, check valve, check valve, reflux valve, retention valve, etc.) that opens under vacuum pressure to allow fluid to be drawn or aspirated into collection container 240. While under positive pressure, duckbill valve 230 prevents fluid from flowing back into the aspiration catheter. Disposed within pressure port 205 is a second backflow prevention device 230′ (e.g., a duckbill valve, one-way valve, check valve, check valve, reflux valve, retention valve, etc.). While fluid is compressed by the advancement of plunger 215 within pressure port 205, fluid is prevented from flowing back through the pressure port. Optionally, there can be a small hole or opening in duckbill valve 230′ that, when closed, allows slightly more of the generated positive pressure to pass therethrough while still preventing fluid from flowing back. Because the plunger or piston 215 is in an RHV attached to the aspiration catheter 200, there is minimal decay of the positive pressure before it reaches the distal tip / end. Therefore, a minimal volume of fluid needs to be displaced (i.e., compressed) by the plunger or piston 215 to achieve a relatively high level of positive pressure at the distal tip / end of the aspiration catheter.

[0023] Yet another example of a cyclical suction system according to the present disclosure, shown in FIGS. 3A and 3B, also eliminates the need for a vacuum pump. A cyclical suction pressure waveform is generated using a bellows-type ("flexi") container fluidly connected to an inlet tube located proximally of a catheter hub 303. The example of FIG. 3A shows an exemplary bellows-type container 305 (e.g., a bellows, bellows, or accordion) that is axially collapsible when subjected to an external axial force applied by an externally disposed linear displacement mechanism 350 (e.g., a linear actuator, a solenoid, a cam, a rotary reciprocating mechanism, a reciprocating mechanism, etc.) secured thereto (FIG. 3B). The bellows-type container 305 preferably has axial resistance such that, in the absence of an external axial compressive force (i.e., when pulled or removed), the bellows-type container 305 automatically restores to its natural or default, uncompressed state (FIG. 3A). During removal of the external axial compressive force shown in FIG. 3A, axial resistance causes the corrugated container 305 to return to its default uncompressed (i.e., axially expanded) state, generating the vacuum pressure intervals of the periodic suction pressure waveform. In response to the solenoid 313 applying sufficient external axial force to overcome the axial resistance, the corrugated container 305 collapses axially, compressing the fluid collected therein and creating the positive pressure intervals, as shown in FIG. 3B. The variable valve 335 allows for depressurization of the system (i.e., venting of positive pressure, which ultimately returns to blood pressure), in preparation for reapplying or restoring vacuum pressure during expansion of the corrugated container 305 to its natural (i.e., uncollapsed) state. Furthermore, if the linear displacement mechanism 350 (e.g., a solenoid) used applies a constant force per stroke, the variable valve 335 can be used to control or vary the amplitude of the positive pressure generated within the system.

[0024] 4A and 4B , yet another exemplary cyclic aspiration system generates a cyclic aspiration pressure waveform using a slidable plunger or piston 415 within a reservoir 405 located proximal to the catheter hub 403, with a one-way valve 430 disposed therebetween. Retraction of the plunger 415 within the reservoir 405 generates vacuum pressure, opening the one-way valve 430 and allowing fluid from the aspiration catheter 400 to be drawn or aspirated therethrough. As the plunger 415 is advanced within the reservoir 405, positive pressure pushing toward the aspiration catheter 400 closes the one-way valve 430, preventing fluid from being injected into the aspiration catheter and preventing clots from being pushed too far forward. The plunger of the piston 415 is intermittently and cyclically displaceable (e.g., retracted or advanced) via a linear displacement mechanism 450 (e.g., a linear actuator, a solenoid, a cam, a rotary reciprocating mechanism, a reciprocating mechanism, etc.) located external to the reservoir 405. Prior to use during an endovascular treatment to capture thrombi (i.e., pre-treatment), the reservoir 405 may be pre-filled or pre-loaded with saline for initial preparation or cleaning (i.e., pre-treatment). During operation, the solenoid 450 intermittently and periodically (i) retracts the plunger or piston 415 into the reservoir 405, generating vacuum pressure and drawing fluid (e.g., blood and / or saline) into the reservoir 405, and (ii) advances the plunger or piston 415 into the reservoir 405, compressing the fluid collected therein and generating positive pressure. The repeated periodic retraction and advancement of the plunger or piston 415 generates a periodic suction pressure waveform with intermittent, periodic intervals of vacuum pressure and positive pressure using a dual pressure generator receptacle without the use of a vacuum pump. Preferably, the fluid collected in the reservoir 405 may be siphoned into a separate collection tank 440 (e.g., a disposable bag) via the inlet tube 420. Variable valve 435 allows depressurization of the system (ie, venting of positive pressure that ultimately returns to blood pressure) in preparation for re-application or restoration of vacuum pressure during retraction of plunger 415 .Additionally, if the linear displacement mechanism (e.g., solenoid 450) applies a constant force per stroke, variable valve 435 can be used to control or vary the amplitude of the positive pressure generated within the system. Variable valve 435 (e.g., a one-way valve) serves the dual function of (i) acting as a one-way valve, only allowing fluid to be delivered to reservoir 440 and preventing fluid from being aspirated from reservoir 440, and (ii) acting as a variable restrictor or pressure control valve, controlling the pressure within reservoir 405 and therefore the pressure delivered to aspiration catheter 400.

[0025] Preferably, the two linear displacement mechanisms 450, 455 are synchronized with each other to enable a seamless transition between positive pressure and vacuum pressure. During operation, FIG. 4A shows the plunger or piston 415 in a retracted state within the reservoir 405, generating intervals of vacuum pressure. In response to the solenoid 450 applying an external axial force, the plunger or piston 415 advances within the reservoir 405, compressing the fluid collected therein and generating intervals of positive pressure. Advantageously, the components of the cyclic aspiration system that are contaminated by blood (e.g., the inlet tube 420, the liquid reservoir 405, the plunger 415, the inlet / auxiliary tube 420, and the collection container 440) are inexpensive and disposable or disposable after a single use (preferably together as a single module or unit), while the reusable, non-disposable electronic components of the linear displacement mechanisms 450, 455 (e.g., the solenoid) are located externally and therefore not contaminated by (physically contacted by) blood.

[0026] Aspects of the present disclosure are also provided by the following numbered paragraphs: Clause 1 A periodic aspiration system for generating a periodic aspiration pressure waveform that alternates between a vacuum pressure below atmospheric pressure and a positive pressure above the vacuum pressure, the periodic aspiration system comprising: a suction catheter (100, 200, 300, 400) having a proximal end and an opposite distal end; and a dual pressure generator receptacle (105, 205, 305, 405) disposed proximally of the suction catheter and connected in fluid communication with the suction catheter (100, 200, 300, 400), the dual pressure generator receptacle (105, 205, 305, 405) having a linear displacement A periodic suction system for receiving a collectable fluid therein, capable of intermittently and periodically applying or removing a compressive force via a mechanism (150, 250, 350, 450), wherein a positive pressure can be generated while the collectable fluid in the dual pressure generator receptacle (105, 205, 305, 405) is subjected to a compressive force, and a vacuum pressure can be generated while the collectable fluid in the dual pressure generator receptacle is not subjected to a compressive force, and wherein a periodic suction pressure waveform can be generated via the dual pressure generator receptacle without the use of a separate vacuum pump.

[0027] Clause 2. The periodic suction system described in clause 1 further comprises an inlet tube (120, 420) positioned proximal to a proximal hub (103, 303, 403) positioned at the proximal end of the suction catheter (100, 400), and the dual pressure generator receptacle (105, 405) and a separate collection container (140, 440) are connected in fluid communication with the inlet tube (120, 420).

[0028] Clause 3. A periodic suction system as described in clause 2, wherein the dual pressure generator receptacle is a syringe (105) or a reservoir (405) having a plunger (115, 415) displaceable therein via a linearly displaceable mechanism (150, 450), and the collection container (140, 440) is a tank or disposable bag in fluid communication with the syringe (105) or reservoir (405) via an inlet tube (120, 420).

[0029] Clause 4. A periodic suction system as described in any of clauses 2 to 3 of claim 2, further comprising a first one-way valve (130', 430') disposed within the inlet tube (120, 420) and preventing fluid collectable within the system from passing distally therethrough into the suction catheter (100, 400) when subjected to positive pressure.

[0030] Clause 5. The periodic suction system described in clause 4, further comprising a second one-way valve (130, 430) that prevents collectable fluid from escaping into the collection container (140, 440) and controls positive pressure to the suction catheter (100, 400).

[0031] Clause 6. The periodic suction system described in clause 1 further comprises a rotary hemostatic valve having an outlet port and a pressure port (205) having a side port (205a), the proximal end of the suction catheter (200) being fluidly connected to the outlet port of the rotary hemostatic valve, the dual pressure generator receptacle being the pressure port (205) of the rotary hemostatic valve, and the linear displacement mechanism periodically engaging with a displaceable plunger (215) within the pressure port (205) of the rotary hemostatic valve.

[0032] Clause 7. The cyclic suction system described in clause 6 further comprises a first one-way valve (230') disposed in the inlet tube and preventing fluid collectable within the system from passing distally through the interior thereof into the suction catheter (200) when subjected to positive pressure.

[0033] Clause 8. The periodic suction system described in clause 7, further comprising a second one-way valve (230) that prevents collectable fluid from escaping into the collection container (240) and controls positive pressure to the suction catheter (200).

[0034] Article 9. The periodic suction system described in clause 1, wherein the dual pressure generator receptacle is a bellows-shaped container (305) having axial resistance, the bellows-shaped container (305) is connected to a proximal hub (303) disposed at the proximal end of the suction catheter (300) via an inlet tube (320), and a linear displacement mechanism (350) applies or removes compressive force to the bellows-shaped container (305) which is movable between an axially collapsed state and an axially expanded state.

[0035] Article 10. 10. A periodic suction system as described in any of clauses 1 to 9, wherein the linear displacement mechanism (150, 250, 350, 450) is external to the dual pressure generator receptacle (105, 205, 305, 405), is not contaminated with blood, and is reusable, while the dual pressure generator receptacle can be contaminated with blood and is disposable after a single use.

[0036] Article 11. A method for using a cyclic aspiration system to generate a periodic aspiration pressure waveform that is an on-off cycle of a vacuum pressure below atmospheric pressure and a positive pressure above the vacuum pressure, the cyclic aspiration system comprising: an aspiration catheter (100, 200, 300, 400) having a proximal end and an opposite distal end; and a dual pressure generator receptacle (105, 205, 305, 405) disposed proximal to the aspiration catheter (100, 200, 300, 400) and connected in fluid communication with the aspiration catheter (100, 200, 300, 400). The method includes the steps of delivering the aspiration catheter (100, 200, 300, 400) through a blood vessel to a target site proximal to a thrombus; generating a periodic suction pressure waveform by intermittently and periodically subjecting collectable fluid receivable therein to application or removal of a compressive force via a linear displacement mechanism (150, 250, 350, 450) using a dual pressure generator receptacle (105, 205, 305, 405), wherein a positive pressure is generated while the collectable fluid in the dual pressure generator receptacle (105, 205, 305, 405) is subjected to the compressive force, and a vacuum pressure is generated while the collectable fluid in the dual pressure generator receptacle (105, 205, 305, 405) is not subjected to the compressive force, and the periodic suction pressure waveform is generateable via the dual pressure generator receptacle (105, 205, 305, 405) without the use of a separate vacuum pump.

[0037] Article 12. The method described in clause 11, wherein the periodic suction system further comprises an inlet tube (120, 420) positioned proximal to a proximal hub (103, 303, 403) positioned at the proximal end of the suction catheter (100, 400), and the dual pressure generator receptacle (105, 405) and the separate collection container (140, 440) are connected in fluid communication with the inlet tube (120, 420).

[0038] Article 13. The method of claim 12, wherein the dual pressure generator receptacle is a syringe (105) or a reservoir (405) having a plunger (115, 415) displaceable therein via a linearly displaceable mechanism (150, 450), and the collection container (140, 440) is a tank or disposable bag in fluid communication with the syringe (105) or reservoir (405) via an inlet tube (120, 420).

[0039] Clause 14. 14. The method of any of clauses 12 to 13, further comprising a first one-way valve (130', 430') disposed in the inlet tube (120, 420) that, when subjected to positive pressure, prevents fluid collectable within the system from passing distally therethrough into the suction catheter (100, 400).

[0040] Article 15. 15. The method of clause 14, further comprising a second one-way valve (130, 430) for preventing collection of fluid in the collection container (140, 440) from escaping and controlling positive pressure to the suction catheter (100, 400).

[0041] Article 16. The method described in clause 11, wherein the periodic suction system further comprises a rotary hemostatic valve having an outlet port and a pressure port (205) having a side port (205a), the proximal end of the suction catheter (200) is fluidly connected to the outlet port of the rotary hemostatic valve, the dual pressure generator receptacle is the pressure port (205) of the rotary hemostatic valve, and the linear displacement mechanism periodically engages with a displaceable plunger (215) within the pressure port (205) of the rotary hemostatic valve.

[0042] Article 17. 17. The method of claim 16, further comprising a first one-way valve (230') disposed in the inlet tube that, when subjected to positive pressure, prevents fluid collectable within the system from passing distally therethrough into the suction catheter (200).

[0043] Article 18. 18. The method of clause 17, further comprising a second one-way valve (230) that prevents collectable fluid from escaping into the collection container (240) and controls positive pressure to the suction catheter (200).

[0044] Article 19. The method of clause 11, wherein the dual pressure generator receptacle is a bellows-shaped container (305) having axial resistance, the bellows-shaped container (305) is connected to a proximal hub (303) attached to the suction catheter (300) via an inlet tube (320), and the linear displacement mechanism (350) applies or removes a compressive force to the bellows-shaped container (305) that is movable between an axially collapsed state and an axially expanded state.

[0045] Article 20. 20. The method of any of clauses 11 to 19, wherein the linear displacement mechanism (150, 250, 350, 450) is external to the dual pressure generator receptacle (105, 205, 305, 405), is not contaminated with blood, and is reusable, while the dual pressure generator receptacle can be contaminated with blood and is disposable after a single use.

[0046] The descriptions contained herein are examples and are not intended to limit the scope of the present disclosure in any way. As described herein, the present disclosure contemplates many variations and modifications of a cyclic aspiration system for generating a cyclic aspiration pressure waveform without using a vacuum pump (e.g., a centrifugal pump, a piston pump, or a diaphragm pump). In particular, the cyclic aspiration system generates a cyclic aspiration pressure waveform using a dual pressure generator receptacle (e.g., a syringe in fluid communication with an inlet tube, a displaceable plunger disposed with a pressure port of an RHV, a bellows-type container, or a reservoir with a displaceable plunger slidable therein). The cyclic aspiration pressure waveform of intermittent, periodic intervals of vacuum pressure (i.e., below atmospheric pressure) and positive pressure (i.e., above vacuum pressure) is generated by intermittently and periodically removing and applying a compressive force to a fluid collected in the dual pressure generator receptacle. Modifications and variations obvious to those skilled in the art from the teachings of the present disclosure are intended to be within the scope of the following claims.

[0047] [Embodiment] (1) A periodic suction system for generating a periodic suction pressure waveform of an on-off cycle of a vacuum pressure below atmospheric pressure and a positive pressure above vacuum pressure, the periodic suction system comprising: an aspiration catheter having a proximal end and an opposite distal end; a dual pressure generator receptacle disposed proximal to the suction catheter and connected in fluid communication with the suction catheter, the dual pressure generator receptacle receiving a collectable fluid therein and capable of being intermittently and cyclically subjected to application or removal of a compressive force via a linear displacement mechanism, the positive pressure being generateable while the collectable fluid in the dual pressure generator receptacle is subjected to the compressive force, and the vacuum pressure being generateable while the collectable fluid in the dual pressure generator receptacle is not subjected to the compressive force; A cyclic suction system, wherein the cyclic suction pressure waveform can be generated via the dual pressure generator receptacle without a separate vacuum pump. (2) The periodic suction system of embodiment 1 further comprises an inlet tube located proximal to a proximal hub located at the proximal end of the suction catheter, and the dual pressure generator receptacle and separate collection container are connected in fluid communication with the inlet tube. (3) The periodic suction system of embodiment 2, wherein the dual pressure generator receptacle is a syringe or reservoir having a plunger displaceable therein via the linearly displaceable mechanism, and the collection container is a tank or disposable bag in fluid communication with the syringe or reservoir via the inlet tube. (4) The cyclic suction system of embodiment 2, further comprising a first one-way valve disposed in the inlet tube that, when subjected to the positive pressure, prevents fluid collectable within the system from passing distally therethrough into the suction catheter. (5) The periodic suction system of embodiment 4, further comprising a second one-way valve that prevents collectable fluid from escaping into the collection container and controls the positive pressure to the suction catheter.

[0048] (6) The cyclic suction system of embodiment 1 further comprises a rotary hemostatic valve having an outlet port and a pressure port having a side port, the proximal end of the suction catheter is in fluid communication with the outlet port of the rotary hemostatic valve, the dual pressure generator receptacle is the pressure port of the rotary hemostatic valve, and the linear displacement mechanism periodically engages with a displaceable plunger within the pressure port of the rotary hemostatic valve. (7) The cyclic suction system of embodiment 6, further comprising a first one-way valve disposed in the inlet tube that, when subjected to the positive pressure, prevents fluid collectable within the system from passing distally therethrough into the suction catheter. (8) The periodic suction system of embodiment 7, further comprising a second one-way valve that prevents collectable fluid from escaping into the collection container and controls the positive pressure to the suction catheter. (9) The cyclic suction system of embodiment 1, wherein the dual pressure generator receptacle is a bellows-shaped container having axial resistance, the bellows-shaped container is connected via an inlet tube to a proximal hub disposed at the proximal end of the suction catheter, and the linear displacement mechanism applies or removes the compressive force to the bellows-shaped container, which is transitionable between an axially collapsed state and an axially expanded state. (10) A cyclic suction system as described in embodiment 1, wherein the linear displacement mechanism is external to the dual pressure generator receptacle, is not contaminated with blood, and is reusable, while the dual pressure generator receptacle can be contaminated with blood and is disposable after a single use.

[0049] (11) A method for using a cyclic aspiration system to generate a periodic aspiration pressure waveform that alternates between a vacuum pressure below atmospheric pressure and a positive pressure above vacuum pressure, the cyclic aspiration system comprising: a suction catheter having a proximal end and an opposite distal end; and a dual pressure generator receptacle disposed proximal to and connected in fluid communication with the suction catheter, the method comprising: delivering the aspiration catheter through a blood vessel to a target site proximal to the thrombus; and generating the periodic suction pressure waveform by using the dual pressure generator receptacle to intermittently and periodically subject collectable fluid received therein to the application or removal of a compressive force via a linear displacement mechanism, wherein the positive pressure is generated while the collectable fluid in the dual pressure generator receptacle is subjected to the compressive force and the vacuum pressure is generated while the collectable fluid in the dual pressure generator receptacle is not subjected to the compressive force, and the periodic suction pressure waveform is generateable via the dual pressure generator receptacle without the use of a separate vacuum pump. (12) The method of embodiment 11, wherein the cyclic suction system further comprises an inlet tube located proximal to a proximal hub located at the proximal end of the suction catheter, and the dual pressure generator receptacle and separate collection container are connected in fluid communication with the inlet tube. (13) The method of embodiment 12, wherein the dual pressure generator receptacle is a syringe or reservoir having a plunger displaceable therein via the linearly displaceable mechanism, and the collection container is a tank or disposable bag in fluid communication with the syringe or reservoir via the inlet tube. (14) The method of embodiment 12, further comprising a first one-way valve disposed in the inlet tube that, when subjected to the positive pressure, prevents fluid collectable within the system from passing distally therethrough into the suction catheter. (15) The method of embodiment 14, further comprising a second one-way valve that prevents collectable fluid from escaping into the collection container and controls the positive pressure to the suction catheter.

[0050] (16) The method of embodiment 11, wherein the cyclic suction system further comprises a rotary hemostatic valve having an outlet port and a pressure port having a side port, the proximal end of the suction catheter is in fluid communication with the outlet port of the rotary hemostatic valve, the dual pressure generator receptacle is the pressure port of the rotary hemostatic valve, and the linear displacement mechanism periodically engages with a displaceable plunger within the pressure port of the rotary hemostatic valve. (17) The method of embodiment 16, further comprising a first one-way valve disposed in the inlet tube that, when subjected to the positive pressure, prevents fluid collectable within the system from passing distally therethrough into the suction catheter. (18) The method of embodiment 17, further comprising a second one-way valve that prevents collectable fluid from escaping into the collection container and controls the positive pressure to the suction catheter. (19) The method of embodiment 11, wherein the dual pressure generator receptacle is a bellows-shaped container having axial resistance, the bellows-shaped container being connected via an inlet tube to a proximal hub attached to the suction catheter, and the linear displacement mechanism applies or removes the compressive force to the bellows-shaped container, which is transitionable between an axially collapsed state and an axially expanded state. (20) The method of embodiment 11, wherein the linear displacement mechanism is external to the dual pressure generator receptacle, is not contaminated with blood, and is reusable, while the dual pressure generator receptacle can be contaminated with blood and is disposable after a single use.

Claims

1. 1. A cyclic aspiration system for generating a cyclic aspiration pressure waveform of an on-off cycle of a vacuum pressure below atmospheric pressure and a positive pressure above vacuum pressure, the cyclic aspiration system comprising: an aspiration catheter having a proximal end and an opposite distal end; a dual pressure generator receptacle disposed proximal to the suction catheter and connected in fluid communication with the suction catheter, the dual pressure generator receptacle receiving a collectable fluid therein and capable of being intermittently and cyclically subjected to application or removal of a compressive force via a linear displacement mechanism, the positive pressure being generateable while the collectable fluid in the dual pressure generator receptacle is subjected to the compressive force, and the vacuum pressure being generateable while the collectable fluid in the dual pressure generator receptacle is not subjected to the compressive force; A cyclic suction system, wherein the cyclic suction pressure waveform can be generated via the dual pressure generator receptacle without a separate vacuum pump.

2. 10. The periodic suction system of claim 1, further comprising an inlet tube located proximal to a proximal hub located at the proximal end of the suction catheter, the dual pressure generator receptacle and a separate collection container being connected in fluid communication with the inlet tube.

3. 3. The periodic aspiration system of claim 2, wherein the dual pressure generator receptacle is a syringe or reservoir having a plunger displaceable therein via the linearly displaceable mechanism, and the collection container is a tank or disposable bag in fluid communication with the syringe or reservoir via the inlet tube.

4. 3. The cyclic aspiration system of claim 2, further comprising a first one-way valve disposed in the inlet tube that, when subjected to the positive pressure, prevents fluid collectable within the system from passing distally therethrough into the aspiration catheter.

5. 5. The cyclic aspiration system of claim 4, further comprising a second one-way valve that prevents collectable fluid in the collection container from escaping and controls the positive pressure to the aspiration catheter.

6. 2. The periodic aspiration system of claim 1, further comprising a rotary hemostatic valve having an outlet port and a pressure port having a side port, wherein the proximal end of the aspiration catheter is in fluid communication with the outlet port of the rotary hemostatic valve, the dual pressure generator receptacle is the pressure port of the rotary hemostatic valve, and the linear displacement mechanism periodically engages with a displaceable plunger within the pressure port of the rotary hemostatic valve.

7. 7. The cyclic aspiration system of claim 6, further comprising a first one-way valve disposed in the inlet tube that, when subjected to the positive pressure, prevents fluid collectable within the system from passing distally therethrough into the aspiration catheter.

8. 8. The cyclic aspiration system of claim 7, further comprising a second one-way valve that prevents collectable fluid in the collection container from escaping and controls the positive pressure to the aspiration catheter.

9. 2. The cyclic suction system of claim 1, wherein the dual pressure generator receptacle is a bellows-type container having axial resistance, the bellows-type container being connected via an inlet tube to a proximal hub disposed at the proximal end of the suction catheter, and the linear displacement mechanism applies or removes the compressive force to the bellows-type container, which is transitionable between an axially collapsed state and an axially expanded state.

10. 2. The cyclic aspiration system of claim 1, wherein the linear displacement mechanism is external to the dual pressure generator receptacle, is not contaminated with blood, and is reusable, while the dual pressure generator receptacle can be contaminated with blood and is disposable after a single use.

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