Automated balloon inflation device for transcatheter heart valve implantation

Abstract

A method of implanting an artificial heart valve includes delivering the artificial heart valve to its native valve annulus while the artificial heart valve is crimped onto a deflated balloon of a delivery device. The method can include advancing fluid into the balloon through the delivery device to inflate the balloon and expand the artificial heart valve within its native valve annulus. The method can include monitoring the pressure within the delivery device while advancing fluid through the delivery device. The method can also include displaying the monitored pressure in real time on a display device while monitoring the pressure.

Description

[[Technical Field]]

[0001] Cross-Reference to Related Applications This application claims the priority benefit of U.S. Provisional Patent Application No. 63 / 343,479, filed on May 18, 2022, the disclosure content of which is incorporated herein by reference. [[Background Art]]

[0002] Valvular heart disease, particularly aortic valvular disease and mitral valvular disease, is a major public health problem in the United States. Valve replacement is one option for treating valvular heart disease. Prosthetic heart valves are well known in the patent literature, including surgical heart valves and collapsible / expandable heart valves intended for transcatheter aortic valve replacement ("TAVR") or transcatheter mitral valve replacement ("TMVR"). Surgical or mechanical heart valves can, for example, be sutured to the patient's native annulus (natural valve annulus) during an open-heart surgical procedure. Collapsible / expandable heart valves are delivered into a patient's body through a tubular delivery device such as a catheter, trocar, or laparoscopic instrument, allowing more invasive procedures such as full thoracotomy and open-heart surgery to be avoided. As used herein, reference to a "collapsible / expandable" heart valve includes heart valves that are formed with a small cross-section to enable delivery to a patient via a tubular delivery device in a minimally invasive procedure and expand to an operable state when positioned in place, as well as heart valves that after construction are first collapsed to a small cross-section for initial delivery to a patient, then expanded to an operable size when positioned in place within the annulus.

[0003] Foldable / expandable artificial heart valves typically take the form of a one-way valve structure (often referred to herein as a valve assembly) mounted on / within an expandable stent. Generally, these foldable / expandable artificial heart valves include self-expanding stents or balloon-expanding stents, which are often made of nitinol or another shape-memory metal or metal alloy (in the case of self-expanding stents), or steel or cobalt-chromium (in the case of balloon-expanding stents). Existing foldable / expandable TAVR devices are known to use a variety of stent configurations, including linear vertical struts connected by “V-shaped sections” as shown in U.S. Patent No. 8,454,685, or rhomboid cell layouts as shown in U.S. Patent No. 9,326,856, both of which are incorporated herein by reference. A one-way valve assembly mounted on / within a stent includes one or more valve leaves and may also include a cuff or skirt. The cuff can be positioned on the inner or inner surface of the stent, the outer or outer surface of the stent, and / or both surfaces. The cuff helps prevent blood from simply flowing around the valve lobe when the valve or valve assembly is not optimally seated on the annulus. The cuff, or any portion of the cuff positioned outside the stent, helps to block leakage around the outside of the valve (known as paravalvular regurgitation or "PV" regurgitation).

[0004] A balloon-inflatable valve is typically delivered to the original valve annulus in a folded (or "crimped") state on top of a deflated balloon in a balloon catheter, with the folded valve covered or uncovered by the sheath above it. Once the crimped prosthetic valve is positioned within the annulus of the original heart valve being replaced, the balloon inflates, forcing the balloon-inflatable valve from its folded or crimped state to an expanded or unfolded state, and the prosthetic valve tends to remain in the expanded shape by the balloon. Usually, once the position of the folded prosthetic valve is determined to be the desired position relative to the original annulus (for example, by visualization under fluoroscopy), a fluid such as saline (gas can also be used, but usually liquid) is forced through the balloon catheter via a manual syringe, causing the balloon to begin filling and expanding, and thus the prosthetic valve above it to expand within the original annulus. Relying entirely on manual balloon inflation may not be optimal, and partial or complete automation of the balloon inflation process may be desirable, for example, to provide more consistent and predictable results for balloon inflation. For example, the predictability of how a balloon-inflatable artificial heart valve will expand can vary significantly depending on how quickly the user inflates the balloon. Such a system could also help provide data that can be collected between many procedures to learn about data that can be used during a procedure, as well as information related to key parameters of balloon inflation that might not otherwise be readily determined from a typical manual process. This information can be collected and used to refine a partially or fully automated balloon inflation process for future procedures. Furthermore, it is desirable that the balloon inflation system (or its associated components) can be reliably degassed before use, preferably using an objective mechanism (not merely visual inspection) to ensure that no more than an acceptable amount of air remains in the catheter before delivery. [Overview of the project]

[0005] According to one aspect of the present disclosure, a method for implanting an artificial heart valve includes delivering the artificial heart valve to the original annulus while the artificial heart valve is crimped onto a deflated balloon of a delivery device. The method may include advancing fluid through the delivery device into the balloon to inflate the balloon and expand the artificial heart valve into the original annulus. The method may include monitoring the pressure within the delivery device while advancing the fluid through the delivery device. The method may also include displaying the monitored pressure in real time on a display device while monitoring the pressure.

[0006] According to another aspect of the present disclosure, an artificial heart valve delivery system may include a handle, a balloon catheter extending from the handle, and a balloon positioned at the distal end of the balloon catheter. A fluid reservoir can be fluidly communicated with a lumen, the lumen is fluidly communicated with the internal volume of the balloon. A motor can be operably connected to the fluid reservoir. An actuator may be provided on the handle, which is operably connected to the motor, such that when the actuator is actuated in a first direction, the motor pushes fluid out of the fluid reservoir through the lumen towards the internal volume of the balloon, and when the actuator is actuated in a second direction opposite to the first direction, the motor pulls fluid out of the internal volume of the balloon towards the fluid reservoir.

[0007] According to another embodiment of the present disclosure, a method for degassing the balloon of a balloon catheter includes (i) withdrawing the plunger of a purge syringe while the purge syringe is in fluid communication with the balloon of the balloon catheter and while the purge syringe is not in fluid communication with a filling syringe containing fluid, and monitoring the vacuum pressure as a function of the plunger displacement as the plunger of the purge syringe is withdrawn to create a pressure-displacement line having a slope. The method may also include (ii) advancing the plunger of a filling syringe while the filling syringe is in fluid communication with the balloon of the balloon catheter and while the filling syringe is not in fluid communication with the purge syringe. The method may further include (iii) advancing the plunger of a filling syringe while the filling syringe is in fluid communication with the purge syringe and while the filling syringe is not in fluid communication with the balloon catheter to push out any remaining air through a one-way valve in fluid communication with the purge syringe. Steps (i) through (iii) can be repeated until the slope of the pressure-displacement line exceeds the threshold slope of the reference pressure-displacement line. [Brief explanation of the drawing]

[0008] [Figure 1A] This is a perspective view of an artificial heart valve stent according to one embodiment of the present disclosure. [Figure 1B] Figure 1A is a schematic front view of a section of the stent. [Figure 1C] Figure 1A is a schematic front view of a section of a stent according to an alternative embodiment of the artificial heart valve. [Figure 1D] This is a front view of the stent section in the folded state shown in Figure 1C. [Figure 1E] This is a front view of the stent section in its expanded state (Figure 1C). [Figure 1F] This is a side view of a portion of the stent according to the embodiment shown in Figure 1C, which is in a folded state. [Figure 1G] This is a side view of a portion of the stent according to the embodiment shown in Figure 1C in its expanded state. [Figure 1H]This is a flattened view of the stent according to the embodiment of Figure 1C, which appears to have been cut and flattened. [Figure 1I] Figure 1C is a front view of the artificial heart valve including the stent. [Figure 1J] Figure 1C is a side view of the artificial heart valve including the stent. [Figure 2A] This is a very schematic diagram of a balloon inflation system according to one aspect of the present disclosure. [Figure 2B] Figure 2A is a very schematic diagram of the rapid fluid extraction mechanism of the balloon inflation system. [Figure 3A] This is a top view of a balloon inflation system according to another aspect of the present disclosure. [Figure 3B] This is a side view of a balloon inflation system according to another aspect of the present disclosure. [Figure 3C] Figures 3A and 3B are perspective views of the handle of the delivery device connected to the balloon inflation system. [Figure 3D] Figure 3C shows the handle of the delivery device. [Figure 3E] Figure 3C shows the handle of the delivery device. [Figure 3F] Figure 3C is a side view of the artificial heart valve crimped onto the deflated balloon of the delivery device. [Figure 3G] This is a diagram of the balloon in its inflated state (Figure 3E). [Figure 3H] Figure 3G shows a balloon with an exemplary pressure sensor used in conjunction with the balloon. [Figure 3I] Figure 3G shows a balloon with an exemplary strain gauge used in the balloon. [Figure 4] Figures 3F and 3G show the pressure versus volume compliance curves of the balloons. [Figure 5] This is a very schematic diagram of the interactions between the various elements involved in the implantation of an artificial heart valve using the device described herein. [Figure 6A] This is an example display screen during the planning steps for artificial heart valve implantation. [Figure 6B] FIG. 12 is an exemplary display screen during a step in a prosthetic heart valve implantation procedure. [Figure 7] FIG. 13 is a very schematic diagram of a degassing system according to an aspect of the present disclosure. [Figure 8] FIG. 14 is a graph showing the slope of vacuum pressure versus syringe displacement during a degassing procedure. DETAILED DESCRIPTION OF EMBODIMENTS

[0009] As used herein, when used in reference to a prosthetic heart valve, the term "inflow end" refers to the end of the prosthetic heart valve into which blood first enters when the prosthetic heart valve is implanted in its intended position and orientation, and the term "outflow end" refers to the end of the prosthetic heart valve from which blood exits when the prosthetic heart valve is implanted in its intended position and orientation. Therefore, in the case of a prosthetic aortic valve, the inflow end is the end closer to the left ventricle, and the outflow end is the end closer to the aorta. It should be noted that the intended position and orientation are used for convenience in describing the valve disclosed herein, but the use of the valve is not limited to the intended position and orientation, and can be deployed in any type of lumen or passageway. For example, although the prosthetic heart valve is described herein as a prosthetic aortic valve, the same or similar structure and function can be adopted for other heart valves such as pulmonary valves, mitral valves, or tricuspid valves. Furthermore, when used in reference to a delivery device or system, the term "proximal" refers to a direction relatively closer to the user of the device or system when used as intended, and the term "distal" refers to a direction relatively farther from the user of the device. In other words, the front end of a delivery device or system, when used as intended, is positioned distally relative to the rear end of the delivery device or system. As used herein, the terms "substantially", "generally", "approximately", and "about" are intended to mean that slight deviations from the absolute are included within the scope of the term so modified. As used herein, a stent may exhibit an "expanded state" and a "collapsed state", which refers to the overall radial size of the stent.

[0010] Figure 1A shows a perspective view of a stent 100 for an artificial heart valve according to one embodiment of the present disclosure. The stent 100 may include a frame extending axially between an inlet end 101 and an outlet end 103. The stent 100 includes three generally symmetrical sections, each section extending about 120 degrees around the circumference of the stent 100. The stent 100 includes three vertical struts 110a, 110b, and 110c, which extend axially substantially parallel to the direction of blood flow through the stent, which may also be called the central longitudinal axis. Each vertical strut 110a, 110b, and 110c may extend substantially over the entire axial length between the inlet end 101 and the outlet end 103 of the stent 100, and each vertical strut 110a, 110b, and 110c may be positioned between two sections and shared by those two sections. In other words, each section is defined by the portion between the two vertical struts of the stent 100. Thus, each vertical strut 110a, 110b, and 110c is also spaced approximately 120 degrees around the circumference of the stent 100. It should be understood that when the stent 100 is used in an artificial heart valve having three lobes, the stent may contain three sections as shown. However, in other embodiments, when the artificial heart valve has two lobes, the stent may contain only two sections.

[0011] Figure 1B shows a schematic diagram of stent section 107 of stent 100, which will be described in more detail herein, and is representative of all three sections. The stent section 107 shown in Figure 1B includes a first vertical strut 110a and a second vertical strut 110b. The first vertical strut 110a extends axially between the first inlet node 102a and the first outer node 135a. The second vertical strut 110b extends axially between the second inlet node 102b and the second outer node 135b. As shown, the vertical struts 110a, 110b can extend over substantially the entire axial length of stent 100. In some embodiments, stent 100 can be formed as a single unit, for example by laser cutting the stent from a tube. The term “node” can refer to the location where two or more struts of stent 100 meet each other. A pair of consecutive inverted V-shaped sections extend between inlet nodes 102a and 102b, and these inverted V-shaped sections include a first inlet inverted V-shaped section 120a and a second inlet inverted V-shaped section 120b, which are connected to each other at the inlet node 105. The first inlet inverted V-shaped section 120a includes a first outer lower strut 122a extending between the first inlet node 102a and the first central node 125a. The first inlet inverted V-shaped section 120a further includes a first inner lower strut 124a extending between the first central node 125a and the inlet node 105. The second inlet inverted V-shaped section 120b includes a second inner lower strut 124b extending between the inlet node 105 and the second central node 125b. The second inlet inverted V-shape 120b further comprises a second outer lower strut 122b extending between the second central node 125b and the second inlet node 102b. Although described as inverted V-shapes, these structures can also be described as half-cells, each half-cell being a semi-rhomboid cell with the open portion of the half-cell located at the inlet end 101 of the stent 100.

[0012] The stent section 107 further includes a first central strut 130a extending between a first central node 125a and an upper node 145. The stent section 107 also includes a second central strut 130b extending between a second central node 125b and an upper node 145. The first central strut 130a, the second central strut 130b, the first inner lower strut 124a, and the second inner lower strut 124b form a rhomboid cell 128. The stent section 107 includes a first outer upper strut 140a extending between a first outer node 135 and a first outflow node 104a. The stent section 107 further includes a second outer upper strut 140b extending between a second outer node 135b and a second outflow node 104b. The stent section 107 includes a first inner upper strut 142a extending between the first outflow node 104a and the upper node 145. The stent section 107 further includes a second inner upper strut 142b extending between the upper node 145 and the second outflow node 104b. The stent section 107 includes an outflow inverted V-shaped section 114 extending between the first outflow node 104a and the second outflow node 104b. The first vertical strut 110a, the first outer upper strut 140a, the first inner upper strut 142a, the first central strut 130a, and the first outer lower strut 122a form a first generally kite-shaped cell 133a. The second vertical strut 110b, the second outer upper strut 140b, the second inner upper strut 142b, the second central strut 130b, and the second outer lower strut 122b form the second generally kite-shaped cell 133b. The first kite-shaped cell 133a and the second kite-shaped cell 133b are symmetrical and opposite each other in the stent section 107. Although the term “kite-shaped” is used above, it should be understood that such a shape is not limited to the strict geometric definition of kite shape. The outflow inverted V-shaped section 114, the first inner upper strut 142a, and the second inner upper strut 142b form the upper cell 134.The upper cell 134 is generally kite-shaped and is axially aligned with the rhomboid cell 128 in the stent section 107. Although specified as separate struts, it should be understood that the various struts described herein may be part of a single, integrated structure as described above. However, in other embodiments, the stent 100 does not need to be formed as an integrated structure, and therefore the struts may be different structures (or parts of different structures) that are connected to one another.

[0013] Figure 1C shows a schematic diagram of a stent section 207 according to an alternative embodiment of the present disclosure. Unless otherwise noted, similar reference numbers refer to similar elements of the stent 100 described above, but within the range of 200 numbers. The stent section 207 is substantially similar to the stent section 107 and includes inlet nodes 202a, 202b, vertical struts 210a, 210b, first inlet inverted V-shaped sections 220a and second inlet inverted V-shaped sections 220b, and outlet nodes 204a, 204b. The structure of the stent section 207 differs from that of the stent section 107 in that it does not include an outlet inverted V-shaped section. The object of the embodiment having such a structure of the stent section 207 shown in Figure 1C is to reduce the force required to expand the outlet end 203 of the stent 200 compared to the stent 100, thereby facilitating uniform expansion to the inlet end 201. The outflow nodes 204a and 204b are connected by a well-directed V-shape formed by a first inner upper strut 242a, upper node 245, and second inner upper strut 242b. In other words, the struts 242a and 242b can form a semi-rhomboid cell 234, with the open end of the semi-cell directed toward the outflow end 203. The semi-rhomboid cell 234 is axially positioned relative to the rhomboid cell 228. Adding the outflow inverted V-shape connected between the outflow nodes 204a and 204b contributes to the addition of material, thereby increasing resistance to changes in the stent shape and requiring more force to expand the stent. By removing material from the outflow end 203, resistance to expansion of the outflow end 203 is reduced, which can promote uniform expansion of the inflow end 201 and the outflow end 203. In other words, the inlet end 201 of the stent 200 does not include a continuous circumferential structure, but rather is a mostly or completely open semicell, with the open portion of the semicell facing the inlet end 201, while the majority of the outlet end 203 includes a substantially continuous circumferential structure via struts corresponding to struts 140a, 140b. All other conditions being equal, the substantially continuous circumferential structure may require greater force to expand compared to a similar but open structure.Therefore, the inlet end 101 of stent 100 may require a greater force to expand radially compared to the outlet end 103. By omitting the inverted V-shaped portion 114, the stent becomes 200, and the force required to expand the outlet end 203 of stent 200 can be reduced to an amount closer to that of the inlet end 201.

[0014] Figure 1D shows a front view of stent section 207 in a folded state, and Figure 1E shows a front view of stent section 207 in an extended state. In Figures 1D and 1E, the stent 200 is shown to have an opaque tube extending through the interior of the stent, for the sole purpose of illustrating the stent, and it should be understood that this tube may represent a balloon into which stent section 207 is crimped. As mentioned above, the stent consists of three symmetrical sections, each section spanning approximately 120 degrees around the circumference of the stent. Stent section 207 shown in Figures 1D and 1E is defined by the region between the vertical struts 210a, 210b. Stent section 207 represents all three sections of the stent. Stent section 207 has an arcuate structure such that when the three sections are connected, they form one complete cylindrical shape. Figures 1F and 1G show a portion of the stent viewed from the side. In other words, the diagrams of stent 200 in Figures 1F and 1G are rotated by approximately 60 degrees compared to the diagrams in Figures 1D and 1E. The diagrams of the stent shown in Figures 1F and 1G are centered on the vertical strut 210b and show approximately half of each of the two adjacent stent sections 207a and 207b on either side of the vertical strut 210b. The sections 207a and 207b surrounding the vertical strut 210b are mirror images of each other. Figure 1F shows the stent sections 207a and 207b in a folded state, and Figure 1G shows the stent sections 207a and 207b in an extended state.

[0015] Figure 1H shows a flattened view of stent 200, including three stent sections 207a, 207b, and 207c, as if the stent had been cut longitudinally and placed flat on a table. As shown, sections 207a, 207b, and 207c are symmetrical to each other, and adjacent sections share a common vertical strut. As mentioned above, stent 200 is shown in a flattened view, but each section 207a, 207b, and 207c has an arc shape spanning 120 degrees, forming a complete cylinder. Figure 1H further shows the lobes 250a, 250b, and 250c connected to stent 200. However, it should be understood that only the connections of lobes 250a-250c are shown in Figure 1H. In other words, each of the three leaflets 250a–250c typically includes a free end, which acts to join with each other to prevent retrograde blood flow through the stent 200, and the free ends move radially outward toward the inner surface of the stent to allow antegrade blood flow through the stent. These free ends are not shown in Figure 1H. Rather, in Figure 1H, the attachment edges of the leaflets 250a–250c are shown by dashed lines. Attachment can be made by any preferred means, but the attachment edges can preferably be sutured to the stent 200 and / or to an intervening cuff or skirt between the stent and the leaflets 250a–250c. Each of the three leaflets 250a, 250b, and 250c extends about 120 degrees from end to end around the stent 200, and each leaflet includes an abdomen that can extend toward the radial center of the stent 200 when the leaflets are joined with each other. Each leaflet extends between the upper nodes of adjacent sections. The first leaflet 250a extends from the first upper node 245a of the first stent section 207a to the second upper node 245b of the second stent section 207b. The second leaflet 250b extends from the second upper node 245b to the third upper node 245c of the third stent section 207c. The third leaflet 250c extends from the third upper node 245c to the first upper node 245a. Thus, each upper node includes the first end of the first leaflet and the second end of the second leaflet connected thereto.In the illustrated embodiment, each end of each valve leaf is connected to its respective node by a suture. However, any connecting means can be used to attach the valve leaf to the stent. It is further intended that the stent may contain any number of sections and / or valve leaves. For example, a stent may contain two sections, each extending 180 degrees around the stent. Furthermore, a stent may contain two valve leaves to mimic a bicuspid valve. It should be noted that each valve leaf may include a tab or other structure (not shown) at the junction between the free end and the attachment end of the valve leaf, and each tab of each valve leaf may be connected to the tab of an adjacent valve leaf to form a commissure. In the illustrated embodiment, the valve leaf commissure is illustrated as being attached to the node where the struts intersect. However, in other embodiments, the stent 200 may include a commissure attachment function incorporated into the stent to facilitate such attachment. For example, the commissure attachment function can be formed at nodes 245a to 245c of the stent 200, and the commissure attachment function includes one or more apertures to facilitate suturing the leaflet commissures to the stent. Furthermore, the leaflets 250a to 250c may be formed from biological materials such as animal pericardium, or from synthetic materials such as ultra-high molecular weight polyethylene (UHMWPE).

[0016] Figures 1I and 1J show an artificial heart valve 206, which includes a stent 200, a cuff 260 connected to the stent 200 (e.g., via sutures), and valve leaves 250a, 250b, 250c attached to the stent 200 and / or the cuff 260 (e.g., via sutures). The artificial heart valve 206 is intended for use in replacing an aortic valve, but the same or similar structures may be used in artificial heart valves for replacing other heart valves. The cuff 260 is located on the luminal or inner surface of the stent 200, although the cuff may instead or further be located on the luminal or outer surface of the stent. The cuff 250 may include an inlet portion located substantially along the inlet portion 201 of the stent 200. Figure 1I shows a front view of valve 206, showing one stent portion 207 between vertical struts 210a, 210b, including a cuff 260, and the outlines of two valve leaves 250a, 250b sutured to the cuff 260. Various methods can be used to suture not only the valve leaves to the cuff, but also the valve leaves and / or the cuff to the stent, many of which are described in U.S. Patent No. 9,326,856, incorporated herein by reference. In the illustrated embodiment, the upper (or outflow) edge of the cuff 260 is sutured to a first central node 225a, upper node 245, and a second central node 225b, which extend along the first central strut 230a and the second central strut 230b. The upper (or outflow) edge of the cuff 260 continues substantially between the second central node of one section and the first central node of the adjacent section. The cuff 260 extends between the upper node 245 and the inlet end 201. Thus, the cuff 260 covers the cells of the stent portion 207 formed by the strut between the upper node 245 and the inlet end 201, including the rhomboid cells 228. Figure 1J shows a side view of the stent 200 including the cuff 260 and the outline of the valve leaf 250b. In other words, the diagram of valve 206 in Figure 1J is rotated by about 60 degrees compared to the diagram in Figure 1I. The diagram shown in Figure 1J is centered on the vertical strut 210b and shows about half of each of the two adjacent stent sections 207a, 207b on either side of the vertical strut 210b.Sections 207a and 207b surrounding the vertical strut 210b are mirror images of each other. As described above, the cuff can be positioned on the inner or inner surface, outer or outer surface, and / or both surfaces of the stent. The cuff ensures that blood does not simply flow around the valve leaflets if the valve or valve assembly is not optimally seated within the annulus. The cuff, or any portion of the cuff positioned outside the stent, can help prevent leakage around the outside of the valve (known as paravalvular regurgitation or "PV" regurgitation). In the embodiments shown in Figures 1I and 1J, the cuff 260 covers only about half of the stent 200, leaving about half of the stent uncovered. This configuration requires less cuff material compared to a cuff that covers more or all of the stent 200. Less cuff material may allow the artificial heart valve 206 to be crimped to a smaller profile when folded. The cuff is intended to cover any amount of surface area of ​​the cylindrical body formed by the stent. For example, the upper edge of the cuff can extend straight around the circumference of any cross-section of the cylindrical body formed by the stent. The cuff 260 can be formed from any suitable material, including biological materials such as animal pericardium, or synthetic materials such as UHMWPE.

[0017] Stents can be formed from biocompatible materials including metals and metal alloys such as cobalt-chromium (or cobalt-chromium) or stainless steel, but in some embodiments, stents may be formed from shape-memory materials such as nitinol. Thus, stents are configured to collapse when crimped to a smaller diameter, for example by the inflation of a balloon within the stent, and / or expand when forcibly released, and the stent substantially maintains its modified shape when at rest. Stents can be crimped to reduce their contour at any given cross-section so as to collapse radially and lengthen (to some extent) axially. Stents can also expand radially and shorten (to some extent) axially.

[0018] Artificial heart valves can be delivered via any suitable transvascular route, such as transapical or transfemoral. Generally, transapical delivery involves a relatively rigid catheter that penetrates the patient's chest and the apex of the left ventricle, resulting in relatively higher trauma compared to transfemoral delivery. In transfemoral delivery, the delivery device containing the valve is inserted through the femoral artery and passed against the flow of blood to the left ventricle. In either delivery method, the valve can first be folded over an inflatable balloon while the balloon is deflated. The balloon can be connected to or placed within the delivery system, which can transport the valve through the body and heart to the aortic valve, with the valve positioned above the balloon (and, in some cases, under a sheath above the balloon). Upon reaching the aortic valve or a position adjacent to it, the surgeon or delivery system operator can position the artificial valve as required within the original annulus, with the artificial valve folded over the balloon. Once the desired alignment is achieved, if a sheath is included above, the sheath can be withdrawn (or advanced) to expose the prosthetic valve, and then the balloon can be inflated so that the prosthetic valve expands radially and at least a portion of the prosthetic valve shortens axially.

[0019] While several embodiments of balloon-expandable artificial heart valves are provided above, it should be understood that the systems, devices, and methods described below, used for inflating, deflating, and / or deflating the balloon of a balloon catheter, may be used with other types of balloon-expandable artificial heart valves different from those described above.

[0020] Referring here to Figure 2A, one embodiment of the automatic balloon inflation device 300 is illustrated. In the illustrated embodiment, the balloon inflation device may include a housing that securely receives a syringe 305 inside. The housing may be mounted such that the body of the syringe 305 is fixed to the housing, and the plunger handle of the syringe 305 is received in a movable member which can be driven axially relative to the housing to advance the plunger into or retract from the body of the syringe 305. The movable member may be operably coupled to a carriage within the housing, the carriage may include a female thread that engages with a male thread of a screw mechanism within the housing, the screw mechanism is operably coupled to a motor within the housing. The motor may be operably coupled to a power source (e.g., a replaceable or permanent battery within the housing, or an AC mains power source). In this embodiment, the motor can be actuated to rotate the screw mechanism, thereby moving the movable member, and thus the plunger handle, forward or backward (depending on the direction of rotation of the screw mechanism) to push fluid out of or into the syringe. For example, the housing of the balloon inflation device 300 may include a deflation button 310 and an inflation button 315. These buttons 310, 315 can be configured such that pressing the corresponding button activates a motor that rotates a screw mechanism in the corresponding rotational direction, thereby causing the plunger handle to move forward or backward at a steady speed (and thus move the volumetric part into or out of the syringe at a generally steady volumetric speed), and the movement stops as soon as the pressure on the button is released. In other embodiments, the motor can be activated by pressing the deflation button 310 or the inflation button 315 once, and the motor can be stopped by pressing the button again. In some embodiments, a third button can be provided that can be activated to stop the motor.During inflation or deflation, syringe 305 can be connected to the balloon inflation port 1010 of balloon catheter 1000, and it should be understood that the lumen of balloon catheter 1000 extends from the balloon inflation port 1010 through a delivery device housing the crimped artificial heart valve into the balloon into which the artificial heart valve is crimped. One advantage of using balloon inflation device 300 compared to a manually operated syringe is that the inflation / deflation rate is constant and controlled inflation and deflation are possible. However, with balloon inflation device 300, the user is still entirely responsible for determining the appropriate volume to press into the balloon to inflate the artificial heart valve.

[0021] The balloon inflation device 300 can be modified to provide further automation. For example, in another embodiment, the balloon inflation device may include an interface that allows the user to input a target volume to which the balloon of the balloon catheter 1000 should be inflated. Once the user has set the target inflation volume and connected the syringe 305 to the housing of the balloon inflation device 300, the user can start the inflation process by simply pressing a single button. The mechanism in which a screw mechanism advances a movable member to push down the syringe handle may be the same as described above, and inflation occurs at a steady rate over the time required to reach the target inflation volume. The balloon inflation device 300 can be programmed to remain steady for a predetermined time once the target inflation volume is reached, and then automatically move the plunger handle of the syringe 305 in the opposite direction to begin deflating the balloon. In such a system, a manual override button may be available to stop the process at any desired time. In a similar embodiment, instead of using a commercially available syringe in an external housing, the balloon inflation device 300 may be integrated into a delivery device having a fluid reservoir instead of a syringe. If such a system is pre-packaged with the artificial heart valve, the target volume can be set before packaging the system, thereby eliminating the need for user input and allowing the entire process described above to be automated by pressing a button or other actuator on the delivery device. One of the advantages of these two alternative embodiments is that, in addition to eliminating the need for manual balloon inflation and deflation, the target volume is reached in a predictable and controlled manner. In other words, the system automatically stops inflation once the target volume is reached, thereby effectively eliminating the possibility of the balloon inflating beyond the target volume, which could lead to balloon rupture and / or damage to patient tissue.

[0022] In some embodiments, once the balloon is inflated and the prosthetic valve expands into its designated place within the annulus, it may be desirable to deflate the balloon very rapidly to minimize the time the inflated balloon fills the annulus and blocks blood flow. It should be noted that during transcatheter prosthetic valve delivery, the heart may be rapidly paced while the prosthetic valve is deployed. Therefore, it may also be desirable, or alternatively desirable, to rapidly deflate the balloon after the prosthetic valve has been deployed to minimize the time the heart is rapidly paced. For example, the balloon inflation device 300 (or a similar version) may include a biasing member such as a compression spring 330 having a first end that abuts against the plunger handle 320 of the syringe 305 and a second end that abuts against a platform 325 which may be on the housing or connected to the syringe 305. A motor drive mechanism schematically shown as mechanism 335 in Figure 2B may operate in a similar manner to those described above to drive the plunger handle 320 distally to inflate the balloon. However, as the plunger handle 320 advances distally, the spring 330 begins to compress, applying a proximal force to the plunger handle 320. This proximal force on the plunger handle 320 is not strong enough to overcome the motor drive mechanism 335 during inflation. However, as the balloon inflates and the artificial heart valve deploys, the motor drive mechanism 335 can be disengaged from the plunger handle 320, causing the spring 330 to depressurize rapidly, thereby biasing the plunger handle 320 proximal and causing a rapid withdrawal of fluid from the balloon back into the body of the syringe 305. Any suitable mechanism can be provided to disengage the motor drive mechanism 335 from the plunger handle 320. For example, if the plunger handle 320 is received (or coupled to) a movable member that is operably coupled to a carriage that engages with a threaded screw mechanism, the coupling between the movable member and the carriage, or between the carriage and the threaded screw, can be disengaged to depressurize the compression spring 330.In other embodiments, a split nut may be used, which is formed as two or more members that can come together to engage with a thread or separate to disengage from a thread, so that the motor drive mechanism 335 can be quickly disengaged from the plunger handle 320. In yet another embodiment, one-sided thread teeth may be provided, which are capable of translating or "rocking" in place to engage with or disengage from the threads of a threaded screw mechanism. However, it should be understood that the compression spring 330 is optional. For example, the speed at which the plunger handle 320 is driven by the motor drive mechanism 335 may be fast enough to avoid any serious patient negative outcomes such as the duration of blood flow occlusion through the balloon (and / or the duration of rapid cardiac pacing) when the plunger handle 320 is driven proximal to deflate the balloon.

[0023] Figures 3A and 3B show another embodiment of the balloon inflation system 400. Similar to the balloon inflation device 300, the balloon inflation system 400 may include a housing 401 that houses one or more components, which may include a motor, one or more batteries, electronics for control and / or communication with other components. The housing 401 may include one or more fixed cradles for receiving a syringe 405. In the illustrated embodiment, the distal cradle 402a is given an open "C" or "U" shaped configuration so that the distal end of the syringe 405 can be snapped into or out of the distal cradle 402a. A proximal cradle 402b may also be provided, which may have a lower "C" or "U" shaped portion hinged to the upper "C" or "U" shaped portion. This configuration allows the proximal end of the outer body of the syringe 405 to snap into the bottom portion of the cradle 402b, and the top portion of the cradle 402b to close and connect to the bottom portion, completely enclosing the outer body of the syringe 405 and locking the syringe 405 into the housing 401. It should be understood that more or fewer cradles of similar or different designs may be included with the housing 401 to help secure the syringe 405 to the housing in any preferred manner.

[0024] The balloon inflation system 400 may include a movable member 406. In the illustrated embodiment, the movable member 406 includes a C-shaped or U-shaped cradle for receiving a plunger handle 420 inside, the cradle being mounted on a carriage that extends at least partially into the housing 401. The carriage of the movable member 406 may generally be cylindrical and may include a female thread that mates with a male thread of a screw mechanism (not shown) in the housing which is operably connected to a motor. In some embodiments, the carriage may have a general shape of a U-shaped beam with a flat surface facing the top. The movable member 406 may be fixed to the housing 401 so as not to rotate via any desired mechanism, so that when the screw mechanism is rotated by the motor, the movable member 406 moves further into the housing 401 or further away from the housing 401, depending on the direction of rotation of the screw mechanism. While the plunger handle 420 is connected to the movable member 406, the forward movement of the movable member 406 pushes the fluid from the syringe 405 towards the balloon, while the backward movement of the movable member 406 draws the fluid out from the balloon towards the syringe. The motor or other drive mechanism may be located inside or outside the housing 401, and it should be understood that any other suitable mechanism may be used to operably connect the motor or other drive mechanism to the movable member 406 to enable axial drive of the plunger handle 420.

[0025] As shown in Figures 3A to 3C, the distal end of the syringe 405 can be connected to a tube 407 that is in fluid communication with the lumen (e.g., of a balloon catheter) leading to the balloon 480 at or near the distal end of the delivery device. The tube 407 can pass fluid (e.g., saline solution) from the syringe 405 to the balloon 480, and vice versa, for example, through one or more fluid ports 485 (shown in Figure 3F) in the shaft of the balloon catheter 490.

[0026] Although not individually numbered in Figures 3A and 3B, the housing 401 may include one or more cables extending from the housing to enable, for example, the transmission of power (e.g., from an AC mains power supply or another component to which the cable is connected) and / or the transmission of data, information, control commands, etc. For example, as will be described in more detail later, one cable may connect the housing 401 to the handle 450 of a delivery device, thereby allowing the control unit of the handle 450 to operate the balloon inflation system 400 in a desired manner. As will be described in more detail later, another cable may connect to a computer display or similar device to provide information regarding the inflation of the balloon 480. However, it should be understood that any transmission of data or information may be provided wirelessly, for example, via Bluetooth or other preferred connection, instead of via a wired connection.

[0027] Referring here to Figures 3D and 3E, the handle 450 of the delivery device may include one or more knobs or actuators for operating different functions of the delivery device. For example, a rotary knob near the center of the handle 450 may allow deflection of the catheter, and other knobs or actuators (e.g., near the proximal end of the handle 450) may allow rotation and / or axial adjustment of the balloon 480 (and the artificial heart valve PHV attached thereto) to help obtain precise positioning between the original annulus and the artificial heart valve PHV before deployment. Although a single shaft is shown and labeled as the balloon catheter 490, it should also be understood that the delivery device may include two or more coaxial catheter shafts to provide desired functionality, including relative axial movement between catheter shafts in a stack.

[0028] Referring further to Figures 3D and 3E, the handle may include an actuator 410 for controlling the inflation and deflation of the balloon 480 via the control of the balloon inflation system 400. For example, the actuator 410 may be in the form of a sliding button, having a neutral center position and being able to be advanced distally to inflate the balloon 480 and pulled proximal to deflate the balloon 480. In one example, the actuator 410 remains in the distal or proximal position after being moved from the neutral position. In another embodiment, the actuator 410 may be biased to the neutral position so that as soon as the user releases the force applied to the actuator 410, the actuator 410 automatically returns to the neutral position, in which no fluid is passed through or withdrawn from the balloon 480. As should be understood, sliding the actuator 410 forward or backward transmits a control signal from the handle 450 to the balloon inflation system 400 (for example, via a cable) so that the motor drives the movable member 406 forward or backward to push fluid toward or withdraw fluid from the balloon 480. Figures 3D and 3E show one example of a sliding actuator 410, but it should be understood that other actuators, such as individual buttons or rotary knobs, may be provided on the handle 450 to enable control of the balloon inflation system 400.

[0029] It should also be understood that actuator 410 can provide a binary control mode in which inflation (or deflation) occurs at a set speed or does not occur at all. In other embodiments, actuator 410 may have variable inflation speed control. For example, the user may be able to push actuator 410 distally (or proximal), and the more the user pushes the actuator distally (or proximal), the faster the balloon inflation system 400 inflates (or deflates) the balloon 480. This variable volumetric flow rate may be desirable to allow the user to have finer control over the inflation or deflation of balloon 480, which may be particularly useful when the balloon is on the verge of reaching a target size / volume.

[0030] Referring to Figure 3F, an example of a PHV artificial heart valve, which may include a stent similar to stent 100, is shown crimped onto the balloon 480 of the balloon catheter 490 while the balloon 480 is in a deflated state. When the actuator 410 is slid distally, the balloon inflation system 400 causes fluid to be pumped, for example, through the lumen of the balloon catheter 490 from the syringe 405 into the balloon 480 and into one or more ports 485 located inside the balloon 480. In a particular illustrated example in Figure 3G, from which the PHV artificial heart valve is omitted, the first port 485 may be one or more apertures in the side wall of the balloon catheter 490, and the second port 485 may be the distal open end of the balloon catheter 490, which can terminate within the internal space of the balloon 480.

[0031] The balloon inflation system 400 can be used in a semi-manual manner in which pressure or other sensors do not provide real-time feedback to the user. In such an example, the distal end of the delivery device can be delivered into the patient's body while the artificial heart valve PHV is crimped onto the deflated balloon 480. For example, with or without a maneuvering mechanism (e.g., a pull wire connecting the handle 450 to the distal end of the balloon catheter 490), the distal end of the delivery device can be advanced through the patient's femoral artery and eventually turned to cross the aortic arch. Once the artificial heart valve PHV is positioned within the original aortic annulus, the balloon 480 can be inflated to deploy the artificial heart valve PHV within the original aortic annulus. This deployment can be performed while the patient's heart is being rapidly paced. To inflate the balloon 480, the user can slide the actuator 410 distally, which sends a signal to the balloon inflation system 400, initiating the distal drive of the movable member 406. This pushes down the plunger handle 420, forcing fluid such as saline solution in the syringe 405 through the tube 407 and into the balloon 480 through the balloon catheter 409, thereby inflating the balloon and expanding the artificial heart valve PHV into the original aortic annulus. The user can visualize this process, for example, under fluoroscopy. Once the user confirms that the artificial heart valve PHV is at the desired size and position, they can slide the actuator 410 proximal to reverse the movement of the movable member 406 in a specific direction, drawing the fluid back from the balloon 480 into the syringe 405 and deflating the balloon 480. With balloon 480 deflated and the artificial heart valve PHV expanded in place, rapid cardiac pacing can be stopped, and the heart can begin beating normally again as the artificial heart valve PHV regulates blood flow between the left ventricle and the aorta. In some embodiments, the user can input a target or maximum inflation volume directly into the balloon inflation system 400 (for example, via a user interface provided therein) or into a computer operationally connected to the balloon inflation system 400.When such a target or maximum inflation volume is used, the motor of the balloon inflation system can be programmed to turn off when the balloon inflation system 400 has pushed out the target inflation volume from the syringe 405. In some embodiments, the target or maximum inflation volume can be manually overridden, for example, if the user determines that additional balloon inflation is required to properly expand the artificial heart valve PHV into the original aortic annulus. It should be understood that the volume of fluid moving through the balloon inflation system 400 can be tracked by any preferred method. In one embodiment, since the inner diameter of the syringe 405 is known and the distance traveled by the movable member 406 is known, the resulting volume coming out of (or entering) the syringe 405 can be determined by a simple calculation. In other embodiments, fluid sensors may be incorporated into the system to help track the total amount of fluid entering or leaving the syringe 405 in real time.

[0032] While the aforementioned use of the balloon inflation system 400 can provide significant advantages, including control and precision, compared to conventional, known, fully manual balloon inflation for implanting an artificial heart valve, the balloon inflation system 400 can also provide additional useful functions by utilizing additional data. For example, the pressure within the balloon catheter line can be actively monitored to provide additional data that can be used during the deployment of the artificial heart valve (PHV). One or more pressure sensors can be provided in the fluid path to obtain pressure data inside the fluid line of the balloon catheter. Such locations include, for example, within the lumen of the balloon catheter at a location inside the handle 450, inside or adjacent to the syringe 405 (e.g., near the tip), or inside the balloon 480 (e.g., directly on the inner surface of the balloon, or inside or outside the portion of the shaft of the balloon catheter 490 surrounded by the balloon 480). In some embodiments, a pressure wire may be provided inside the balloon catheter, for example, the sensor housing may be positioned inside the balloon 480. Figure 3H shows one embodiment in which a pressure sensor 482 is attached to a portion of the shaft of a balloon catheter 490 within a balloon 480, and a wire connection 484, such as an electrical or optical wire connection, connects the pressure sensor 482 to another component to read and / or transmit sensor information. The pressure sensor 482 may be a MEMS-based sensor, but other types of sensors may also be suitable. Placing the pressure sensor 482 within the balloon 480 makes it possible to directly measure the pressure inside the balloon, thereby avoiding potential errors that may occur if pressure measurements are taken at a location further away from the balloon 480, such as in the inflation port or syringe 405. However, it should be understood that it may be possible to provide sufficient measurements even without using a pressure sensor that is not directly installed inside the balloon 480, and that the specific sensing mechanism for measuring the real-time pressure inside the balloon catheter can take any other suitable form.

[0033] It may be desirable to determine the area and / or diameter of the balloon 480 during inflation. One way to determine the area and / or diameter of the balloon 480 is based on a previously determined relationship between pressure or volume and diameter. For example, for a balloon 480 having a particular structure, a generally applicable correlation can be determined, thereby allowing the area and / or diameter of the balloon 480 to be estimated based on a known correlation between pressure or volume and size, based on the calculated volume that has passed through the balloon 480. Thus, if the final desired size of the artificial heart valve PHV is known, an algorithm based on that correlation can be applied to determine the total volume to be pressed into the balloon 480 (or the pressure required to reach the desired size). In other embodiments, the balloon 480 may be provided with a sensor that provides information about the diameter of the balloon 480. For example, as shown in Figure 3I, one or more strain gauges 486 can be attached to the outer wall of the balloon 480, or otherwise attached, to provide a direct measurement of the diameter of the balloon 480. The strain gauges 486 may be mounted radially to measure hoop strain or axially to measure diameter. Generally, when the requirement is to measure the diameter, mounting radially may be preferable to mounting axially. The general formula for radial strain in a cylindrical pressure vessel is that radial strain is equal to the product of pressure and radius divided by the product of elastic modulus and wall thickness. Axial strain is half of radial strain and can therefore be used as a less direct measure of radial strain, but this may be less preferable.

[0034] Figure 4 shows the balloon compliance curve for balloon 480, illustrating the relationship between balloon pressure and balloon volume. The solid line represents the baseline or "outside air" pressure-volume curve 510 when balloon 480 is inflated without contact with other structures. However, when balloon 480 contacts a surface such as the aortic valve annulus, the pressure-volume curve shifts from the baseline (shown by the dashed line 520). Curves 510 and 520 are identical before balloon 480 inflates and contacts the original aortic valve annulus. However, upon contact, the pressure-volume curve shifts by a certain amount from the baseline 510, and this change or delta is represented by the arrow 530. This delta 530 is the result of the original tissue compliance adding compressive force to the expanded balloon. This information can be used to help determine when the artificial heart valve (PHV) has expanded to the desired amount. For example, a specific amount of deviation 530 between the baseline pressure-volume curve 510 and the actual pressure-volume curve 520 during implantation can be determined as the amount of deviation 530 corresponding to optimal prosthetic heart valve PHV expansion within the aortic annulus. This desired value of deviation 530 can be determined, for example, through trials across multiple patients or by analysis of data from numerous actual implantations.

[0035] As described above, the volume of fluid entering the balloon 480 from the syringe 405 can be tracked in real time, and the pressure can also be tracked in real time via one or more of the pressure sensors described above. Therefore, during valve implantation using the artificial heart valve PHV and balloon inflation system 400, a real-time pressure-volume curve 520 can be displayed for the user to refer to, along with the expected baseline pressure-volume curve 510, and the user can use the displayed data to confirm the desirability of the procedure or, if necessary, modify the procedure based on that data.

[0036] For example, Figure 5 is a schematic diagram of a procedure setup including a first user such as a physician 600, a second user such as a support staff member 610, a treatment table 620 for the patient, one or more computers and / or displays 630, a balloon inflation system 400, and a delivery device including a handle 450. Some of the various interactions within the setup are briefly described below before a further detailed explanation of specific examples of intraoperative use of data obtained during the procedure. As mentioned above and repeated here, fluid can flow in either direction between the balloon inflation system 400 and the handle 450 of the delivery system, and instruction signals to activate the balloon inflation system 400 can be transmitted from the handle 450 to the balloon inflation system 400. The physician 600 may manually control the delivery system, including implanting the artificial heart valve PHV into the patient's body on the table 620 by using the handle 450, such as by controlling the inflation and deflation of the balloon 450 via the actuator 410. During the procedure, all data obtained from the procedure, such as the volume moved from the balloon inflation system 400 toward (or vice versa) the balloon 480, the current area of ​​the balloon 480 (which can be calculated based on the fluid volume), and the current pressure in the system, can be transmitted to and / or displayed on one or more computers and / or displays 630. As described above, data transmission can be done via a wired or wireless connection. The physician 600 can view the display 630, which may include not only the data described above but also other information such as fluoroscopic images of the patient's anatomical structure. Support personnel 610 can also view the data on the display 630, and either the physician 600 or the support personnel 610 can input parameters such as the target volume for inflation of the balloon 680 via the computer and / or display 630.The computer and / or display 630 can then communicate such parameters to the balloon inflation system 400, for example, by setting a target volume so that the balloon inflation system 400 does not inflate the balloon 480 beyond the target volume unless either user 600, 610 overrides the balloon inflation system 400.

[0037] Figure 6A shows an exemplary screen that may be displayed on a computer and / or display 630 as part of the planning stage before implanting a PHV artificial heart valve in a patient. This exemplary screen allows for one or more inputs to be made for use during the procedure. One exemplary input is the target annular area, which represents the patient's original annular size. In this particular example, the entered value is 623 mm². 2Another exemplary input is the desired oversursize percentage of the artificial heart valve PHV. In other words, it is often desirable to target an area / size of the artificial heart valve PHV that is larger than the patient's original annular area / size in order to generate sufficient friction to help keep the artificial heart valve PHV in place during normal operation of the artificial heart valve PHV. In this particular example, the value entered for the oversize percentage is 5.3%. It should be understood that all numbers and values ​​provided with respect to Figures 6A and 6B are merely illustrative and not intended to be limiting, but rather to show one example of inputs and outputs to better illustrate the relevant concepts. Based on the inputs during the planning phase, several outputs may be provided, such as the target area of ​​the artificial heart valve PHV, which can be calculated by applying the oversize percentage to the patient's annular area for consideration and verification by the physician 600 and / or support staff 610. The outputs may also suggest a particular size of artificial heart valve PHV. For example, artificial heart valve PHVs are usually offered in different size options, and the physician 600 selects the appropriate size option for a particular patient. In this example, a PHV (heart valve) size of 29 mm is recommended based on the input. Another output that can be provided to users 600, 610 is the proposed total inflation volume to be pushed out from the balloon inflation system 400 to achieve the desired expansion size of the PHV. In this particular example, a total inflation volume of 33 mL is proposed. The proposed inflation volume can be provided, for example, based on a predetermined correlation derived from a test relating the inflation volume to the valve area when the balloon 480 is inflated. Yet another output that can be provided is the target pressure of the balloon 480 to achieve the desired expansion size of the PHV. In this particular example, the target pressure is provided as 6.3 atmospheres. While various recommended values ​​are output based on the input data, it should be understood that physician 600 can exercise control to override the recommended values ​​based on their own experience.

[0038] Figure 6B shows an exemplary screen that may be displayed on a computer and / or display 630 as part of the in-procedure stage in which an artificial heart valve PHV is implanted in a patient, following the planning stage shown in Figure 6A. The in-procedure screen in Figure 6B may display the current status of the procedure, for example, "inflating" or "deflating," along with the patient's annular area and selected size of the artificial heart valve PHV from the planning stage in Figure 6A. The in-procedure screen in Figure 6B may display multiple sections that provide current procedure parameters versus target procedure parameters to help users 600, 610 understand the progress of the artificial heart valve PHV deployment. For example, the valve area section may provide the target inflated size / area of ​​the artificial heart valve PHV compared to the current inflated size / area of ​​the artificial heart valve PHV during balloon 680 inflation. The illustrated screen 630 is 326 mm 2 Compared to the current inflated size of the artificial heart valve PHV, 656mm 2 This displays the previously selected target size. In addition to providing a value, it can also display graphs such as progress bars showing the current expansion size as a percentage of the patient's annular size compared to the desired expansion size as a percentage of the patient's annular size. In this example, the target value from the planning stage (e.g., 105.4% of the patient's annular size), which is a 5.4% oversize, is shown in the progress bar along with the current status (e.g., the size of the PHV prosthesis valve during treatment, which is 56.0% of the patient's annular size). Similar information panels, including progress bars, can be provided for other parameters, such as the current balloon pressure (e.g., 6.0 atmospheres) versus the planned target balloon pressure (e.g., 6.4 atmospheres). Another information panel for the current expansion volume (e.g., 27.2 mL at the illustrated stage of treatment) versus the target expansion volume (e.g., 33.2 mL from the planning stage) can be provided, for example, via a progress bar including an indicator of the target expansion volume, along with a graph display.

[0039] Figure 6B also shows a graph plotting the pressure inside balloon 480 versus the area of ​​balloon 480 as the treatment continues. Similar to the compliance curve in Figure 4, the baseline pressure-area curve 510 can be provided as a static known relationship expected when balloon 480 is inflated in “open air”. As balloon 480 inflates, the pressure is detected while the area is detected (e.g., using strain gauge 486) or calculated (e.g., based on a known correlation between the fluid volume and area of ​​balloon 480), so that the actual treatment pressure-area curve 520 can be plotted. As shown in Figure 6B, this results in a deviation 530 of the treatment pressure-area curve 520 from the baseline pressure-area curve 610. The large deviation 530 shown in Figure 6B is for illustrative purposes only, and it should be understood that the size of deviation 530 shown is not intended to represent the level of deviation actually expected. Nevertheless, the deviation 530 between the baseline curve 510 and the treatment curve 520 can provide users 600, 610 with important information that can be used to confirm that the treatment is progressing as intended, or otherwise, that potential problems have arisen that need to be investigated and / or addressed. For example, as described above, a known target deviation 530 between the baseline curve 510 and the treatment curve 520 can be understood as a set or desired deviation. If the illustrated deviation 530 is close to or equal to the target deviation 530, and all other target parameters (e.g., size, balloon pressure, and / or inflation volume of the artificial heart valve PHV) are at or close to their target values, then physician 600 can determine that the treatment has achieved all its goals and that the artificial heart valve PHV has been properly deployed. It should be understood that physician 600 may utilize other information, including fluoroscopic images or their own general experience and knowledge, to aid in this determination. However, if the treatment pressure-area curve 520 deviates significantly more than expected from the baseline curve 510, such deviation 530 may indicate a potential problem.For example, in the example illustrated in Figure 6B, the pressure of balloon 480 is rising much faster than expected, meaning that balloon 480 and the prosthetic heart valve PHV are being subjected to significantly greater forces than expected, even though the prosthetic heart valve PHV is only partially expanding toward the target size. This could be a result of the original tissue compressing the prosthetic heart valve PHV. Possible reasons for this deviation include, for example, that the patient's annulus size was not measured correctly and / or that the calcification of the original valve is significantly greater than expected. If physician 600 continues to inflate balloon 480 despite the large deviation 530 being displayed, there is a risk of rupture of the annulus and / or balloon 480. Therefore, physician 600 can use the actuator 410 on the handle 450 to pause the inflation of balloon 480, assess the situation, determine the cause of the deviation 530, and adjust the treatment accordingly. In some embodiments, physician 600 or support staff 610 can interact with a computer and / or display 630 to update the target parameters based on information obtained from the assessment after pausing the inflation. In some embodiments, a physician 600 or support staff 610 may rely on live fluoroscopic images for valve expansion, and if the artificial heart valve is considered to be fixed, the balloon may be deflated for further investigation, for example, using radiographic imaging and contrast agent injection.

[0040] In some embodiments, the computer and / or display 630 can be programmed to provide alerts to users 600, 610 when a parameter is approaching, at, and / or exceeding a target parameter. Such alerts may be merely informative or may trigger a change in action. For example, when the detected pressure of balloon 480 reaches a target pressure (or, otherwise, exceeds the target pressure, or exceeds the target pressure by a predetermined buffer value, e.g., 5%), the computer and / or display 630 may create an alert that simply informs that the target pressure has been reached or exceeded (by any amount or a predetermined buffer amount), or it may also create an alert that signals the balloon inflation system 400 to stop inflating balloon 480. If an alert triggers such action, users 600, 610 may override the alert by, for example, interacting with the computer and / or display 630, thereby dismissing the alert, and then, if deemed appropriate, continue inflating balloon 480. Other similar types of alerts for other target values ​​can be provided in the same manner.

[0041] Information from a procedure can not only be useful for that particular procedure, but data from numerous procedures can also be aggregated to inform how to optimize subsequent procedures. For example, an information database (preferably with anonymized patient information) can be created that stores information related to the outcome of a procedure, along with parameters that occurred during that particular procedure. As one specific example, the effectiveness of inflating a balloon 480 to a specific pressure and size, taking into account the size of the patient's original aortic annulus, can be stored in the database, along with the resulting effectiveness of the implant. With sufficient data, desired target parameters for future patients can be determined based on the results of previous procedures. For example, if a patient of a certain age, sex, and with a specific size of original aortic annulus is a candidate for artificial heart valve PHV implantation, the patient's information can be compared to other similar patients who have undergone artificial heart valve PHV implantation, and the target parameters for the future patient's procedure can be based, at least in part, on actual parameters found in previous similar patients who have successfully undergone artificial heart valve PHV implantation. As more data is accumulated, more accurate and sophisticated algorithms can be created to predict target procedure parameters to optimize patient outcomes for individual patients. For example, with sufficient data from previous procedures, the system may become highly sensitive and be able to determine subtle changes in the delivery and / or deployment of the artificial heart valve (PHV) based on recognizing patterns in detected pressure changes. For instance, the system could warn the user of initial contact with tissue based on subtle pressure reading changes during the deployment of the PHV into the annulus. Characteristic pressure readings may also be obtained in other situations, such as contact with highly calcified tissue or rupture of any original tissue due to the balloon's expansion force. The system could warn the user of each of these scenarios based on the detected characteristic pressure change readings.Furthermore, it should be understood that these characteristic pressure change readings are not necessarily limited to the deployment phase of the artificial heart valve (PHV), but may also be detected during delivery after the PHV has been introduced into the vascular system. For example, during PHV delivery, the system may detect characteristic pressure change readings indicating several events, such as the movement of the PHV relative to the balloon or contact between the PHV and the luminal tissue of the vascular system.

[0042] While the balloon inflation system described above can offer significant utility in inflating balloon 480 during implantation of the artificial heart valve (PHV), the balloon inflation system may also be useful in preparing the balloon catheter for subsequent use, such as degassing the system. During use of the balloon catheter 490 described above, the internal fluid line extending into syringe 405 within the balloon catheter 490 is a closed system. Generally, it is important that the amount of air in that closed system is minimized. The presence of air in the system can lead to problems or potential problems. For example, if balloon 480 ruptures and there is air in the system, the air may be released into the bloodstream, potentially causing an obstruction of the blood flow, resulting in a stroke or another medical crisis. Furthermore, the presence of air in the system may reduce the accuracy of pressure or other readings compared to when there is no air in the system (or the air is at a minimum acceptable level). Currently, the degassing of balloon catheters before use is performed manually by first vacuuming the catheter with a syringe, then injecting fluid into the catheter with another syringe, repeating this cycle to fill the catheter with fluid and purge any remaining air. However, visual inspection is performed to ensure that there is no air in the balloon catheter (or that the air level is at a minimum acceptable level), but this is a relatively subjective analysis and may carry a potentially high risk of error when human factors are involved. The balloon inflation system described herein can automate the degassing process while also providing a more objective, data-driven confirmation of the amount of air remaining in the balloon catheter following the degassing procedure.

[0043] Figure 7 is a schematic diagram of a degassing system including a filling syringe 405 and a purge syringe 705. The filling syringe 405 and the purge syringe 705 may be substantially identical, and each may be part of a balloon inflation system similar to the system 400 described above. Each syringe 405, 705 can be fluidly connected to a balloon catheter 490 via a three-way stopcock valve 730, which allows any component of the system to be fluidly isolated from the other two components. An air intake section 710 can be positioned between the purge syringe 604 and the valve 730, and a one-way check valve 720 is positioned downstream of the air intake section 710.

[0044] In the exemplary use of the degassing system shown in Figure 7, the balloon catheter 490 is initially empty of fluid. The inflation syringe 405 is pre-filled with the desired fluid (typically saline) with the inflation syringe plunger 408 positioned proximal, and the plunger 708 of the purge syringe plunger 708 is fully advanced distally. While in this position, the syringes 405 and 705 are connected to the balloon catheter 490 via a three-way valve 730. The three-way valve 730 is positioned such that the syringes 405 and 705 are in fluid communication with each other but isolated from the balloon catheter 490. While the three-way valve 730 is in this position, the plunger 408 of the inflation syringe 405 is pushed down, and the fluid is pushed toward the purge syringe 705. During this step, air in the line is purged through the air intake 710 and the check valve 720. During this step, it should be understood that a relatively small proportion of the fluid in the inflation syringe 405 may escape from the inflation syringe 405. Next, the three-way valve 730 is positioned to fluidly connect the purge syringe 705 and the balloon catheter 490, isolating the inflation syringe 405 from other components. The plunger 708 of the purge syringe 705 is withdrawn, creating a vacuum within the balloon catheter 490. During this step, sometimes referred to as the first step, the pressure within the balloon catheter 490 can be measured and recorded as a function of the displacement of the purge syringe plunger 708 using any suitable pressure sensor device, including those described above. While the vacuum is maintained, the three-way valve 730 can be positioned to fluidly connect the balloon catheter 490 and the inflation syringe 405, isolating the purge syringe 705. During this step, sometimes referred to as the second step, the plunger 408 is advanced distally to push fluid into the balloon catheter 490 (or to draw fluid in by vacuum). The three-way valve is then positioned to fluidically connect syringes 405 and 705 and isolate the balloon catheter 490.In this step, sometimes referred to as the third step, the plunger 408 can be pushed down to expel the air trapped in the air intake 710 from the check valve 720. The processes of the steps referred to as the first, second, and third steps can be repeated in sequence, with the pressure-to-plunger displacement 708 being measured and recorded during the first step of each cycle.

[0045] As described above, pressure-versus-displacement measurements are recorded during each cycle of the degassing process as the purge syringe 705 draws a vacuum while maintaining fluid communication with the balloon catheter 490. When there is air in the balloon catheter 490, the air in the system spreads into the purge syringe 705, so the vacuum pressure achieved during this first step is relatively small. However, during each cycle of the steps referred to as the first, second, and third steps, the air is purged from the system. Therefore, in the second time the purge syringe 705 draws a vacuum, there is less air in the system than in the preceding cycle, but the vacuum pressure achieved is greater than in the first cycle. As the cycle is repeated and more air is purged from the system, the vacuum pressure generated by a given displacement of the purge syringe plunger 708 increases. As shown in Figure 8, the slope of the vacuum pressure-versus-displacement relationship increases as more air is removed from the system during each purge cycle. Since these slopes generally follow a mathematical model, a threshold slope can be determined that represents the point at which the amount of air remaining in the balloon catheter 490 is at an acceptable level. Thus, the purge cycle can be continued until the slope of vacuum pressure versus syringe displacement is equal to or greater than the minimum threshold slope. When the slope of vacuum pressure versus syringe displacement is equal to or greater than the minimum threshold slope, the balloon catheter 490 is sufficiently purged, and therefore no more air than an acceptable amount remains in the balloon catheter 490. In a similar, but alternative, embodiment, a minimum vacuum level for a given syringe displacement may be set as the threshold level that, when exceeded, indicates that no more air than an acceptable level remains in the balloon catheter 490.

[0046] It should be understood that the use of an electric syringe system for performing degassing, and the measurement of the relationship between vacuum pressure and displacement of the purge syringe, each method has its own advantages and may be used separately or in combination. For example, automation of the degassing system simplifies the preparation of the balloon catheter 490, even if the final confirmation of air in the system is performed manually by visual inspection. Similarly, even if degassing is performed manually using a syringe, the need to rely on visual inspection to confirm that the balloon catheter 490 has been properly degassed can still be eliminated by utilizing pressure-versus-displacement measurements. Most preferably, automation is combined with pressure measurement to provide a simple and rapid degassing process that relies on objective measurement to determine when the balloon catheter 490 has been properly degassed. Finally, although the degassing system described in relation to Figure 7 is shown as a separate component, it should be understood that this system can be incorporated into the handle 450 of the delivery system so as not to require a physically separate system to perform the degassing procedure.

[0047] According to one aspect of this disclosure, a method for implanting an artificial heart valve is: While the artificial heart valve is crimped onto the deflated balloon of the delivery device, the goal is to deliver the artificial heart valve to the original valve annulus, The fluid is advanced into the balloon through a delivery device, inflating the balloon and expanding the artificial heart valve into the original valve annulus. Monitoring the pressure within the delivery device while advancing the fluid through the delivery device, While monitoring the pressure, the monitored pressure is displayed in real time on the display device, including and / or Displaying the monitored pressure in real time on a display device includes displaying the monitored pressure as a function of the balloon area as a treatment curve, and / or The balloon area is determined based on the monitored pressure, which is determined by measuring the pressure in the fluid line through which the fluid is moving, and / or The balloon area is estimated based on the volume of fluid advancing through the delivery device, and / or The area of ​​the balloon is determined based on strain gauges attached to the balloon, and / or The method includes displaying a reference curve of pressure as a function of balloon area on the display device, and / or The reference curve is based on the expected relationship between the pressure of the balloon and the area of ​​the balloon when the balloon is expanded in free space, and / or This method includes monitoring the difference between a treatment curve and a reference curve while advancing fluid through a delivery device to expand an artificial heart valve, and / or This method involves advancing the fluid through the delivery device by activating an actuator in the handle of the delivery device, and / or Activating the actuator in the handle of the delivery device sends a signal to an electric housing containing a syringe that holds the fluid, which in turn causes the electric housing to push down the plunger of the syringe.

[0048] According to another aspect of this disclosure, the artificial heart valve delivery system is The handlebars and A balloon catheter extending from the handle, A balloon positioned at the distal end of the balloon catheter, A fluid reservoir having fluid communication with a lumen, the lumen having fluid communication with the internal volume portion of a balloon, and a fluid reservoir, A motor operably connected to a fluid reservoir, An actuator in a handle, which is operably connected to a motor, such that when the actuator is actuated in a first direction, the motor pushes fluid out of the fluid reservoir through the lumen towards the internal volume of the balloon, and when the actuator is actuated in a second direction opposite to the first direction, the motor pulls fluid out of the internal volume of the balloon towards the fluid reservoir. It includes and / or The fluid reservoir and motor are housed within the handle, and / or The fluid reservoir is located inside the syringe, the syringe is connected to a housing that receives the syringe, the motor is positioned inside the housing, and / or This system includes a pressure sensor configured to determine the pressure inside the balloon, and / or The pressure sensor is positioned directly inside the balloon, and / or This system is equipped with strain gauges attached to a balloon.

[0049] According to yet another aspect of this disclosure, a method for degassing the balloon of a balloon catheter is: (i) Withdraw the plunger of the purge syringe while the purge syringe is in fluid communication with the balloon of the balloon catheter and while the purge syringe is not in fluid communication with the filling syringe containing the fluid, and create a pressure-displacement line with a slope by monitoring the vacuum pressure as a function of the plunger displacement as the plunger of the purge syringe is withdrawn, (ii) Advance the plunger of the filling syringe while the filling syringe is in fluid communication with the balloon of the balloon catheter and while the filling syringe is not in fluid communication with the purge syringe. (iii) Advance the plunger of the filling syringe while the filling syringe is in fluid communication with the purge syringe and while the filling syringe is not in fluid communication with the balloon catheter, to expel any remaining air through the one-way valve in fluid communication with the purge syringe, Repeat steps (i) through (iii) until the slope of the pressure-displacement line exceeds the threshold slope of the reference pressure-displacement line, including and / or The vacuum pressure is monitored using a pressure sensor that is in fluid communication with the purge syringe, and / or The plunger of the filling syringe and the plunger of the purging syringe are each operably connected to a motor system, and / or The steps of withdrawing the plunger of the purge syringe and advancing the plunger of the filling syringe are performed automatically via a motor system, and / or A three-way valve is positioned between the filling syringe, the purging syringe, and the balloon catheter, and the three-way valve is operable to fluidly connect any two of the filling syringe, the purging syringe, and the balloon catheter at a given moment.

[0050] Although the present invention has been described herein in relation to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the present invention. Therefore, it should be understood that numerous modifications can be made to the exemplary embodiments and other arrangements can be devised without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. The handlebars and A balloon catheter extending from the handle, A balloon positioned at the distal end of the balloon catheter, A fluid reservoir having fluid communication with a lumen, wherein the lumen is in fluid communication with the internal volume portion of the balloon, A motor operably connected to the fluid reservoir, An actuator in the handle, which is operably connected to the motor, such that when the actuator is operated in a first direction, the motor pushes fluid from the fluid reservoir through the lumen toward the internal volume of the balloon, and when the actuator is operated in a second direction opposite to the first direction, the motor pulls fluid out from the internal volume of the balloon toward the fluid reservoir, A pressure sensor configured to detect the pressure inside the balloon, Equipped with, The artificial heart valve delivery system is operably connected to a display device and, while the balloon is inflating, when the pressure sensor detects the pressure inside the balloon, it is configured to display both (i) a baseline pressure curve and (ii) a pressure curve during the actual procedure. (a) The baseline pressure curve is the pressure-area curve expected when the balloon is inflated with outside air, and (b) The pressure curve during the actual procedure is a pressure-area curve, in an artificial heart valve delivery system.

2. The artificial heart valve delivery system according to claim 1, wherein the fluid reservoir and the motor are housed within the handle.

3. The artificial heart valve delivery system according to claim 1, wherein the fluid reservoir is located in a syringe, the syringe is connected to a housing that receives the syringe, and the motor is positioned within the housing.

4. The artificial heart valve delivery system according to claim 1, wherein the pressure sensor is positioned directly within the balloon.

5. The artificial heart valve delivery system according to claim 1, further comprising a strain gauge attached to the balloon.

6. The artificial heart valve delivery system according to claim 1, wherein the area of ​​the pressure-area curve during the actual procedure is determined using a strain gauge on the balloon.

7. The artificial heart valve delivery system according to claim 1, wherein the area of ​​the pressure-area curve during the actual procedure is calculated based on a known correlation between the volume of the fluid and the area of ​​the balloon.

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