Transcatheter Prosthetic Heart Valve Delivery System and Method with Expandable Stability Tube

• US 20110257733A1
• Filed: 04/19/2010
• Published: 10/20/2011
• Est. Priority Date: 04/19/2010
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Dwork, Joshua
• Granted Patent: US 8,465,541 B2
• Time in Patent Office: Days
• US Class Current: 623/2.11
• CPC Class Codes: A61F 2/2412 with soft flexible valve members, e.g. tissue valves shaped like natural valves check valves with flexible valve members in general F16K15/14
• CPC Class Codes: A61F 2/2418 Scaffolds therefor, e.g. support stents
• CPC Class Codes: A61F 2/2436 Deployment by retracting a sheath
• CPC Class Codes: A61F 2002/9665 with additional retaining means

Abstract

A device for percutaneously delivering a stented prosthetic heart valve. The device includes an inner shaft assembly, a delivery sheath assembly, an outer stability tube, and a handle. The sheath assembly is slidably disposed over the inner shaft, and includes a capsule and a shaft. The capsule compressively contains the prosthesis over the inner shaft. The stability tube is slidably disposed over the delivery sheath, and includes a distal region configured to be radially expandable from a first shape having a first diameter to a second shape having a larger, second diameter. In a first delivery state, the distal region assumes the first shape, providing a low profile appropriate for traversing a patient'"'"'s vasculature. In a second delivery state, the distal region has the expanded diameter second shape, sized to receive the capsule, such as when retracting the capsule to implant the prosthesis.

Claims

1. A delivery device for percutaneously delivering a stented prosthetic heart valve, the prosthetic heart valve being radially self-expandable from a compressed arrangement to a normal, expanded arrangement, the delivery device comprising:

an inner shaft assembly including a coupling structure configured to selectively engage a stented prosthetic heart valve;

a delivery sheath assembly slidably disposed over the inner shaft assembly and including a distal capsule and a proximal shaft, when the capsule is configured to compressively contain a stented prosthetic heart valve in a compressed arrangement;

an outer stability tube slidably disposed over the delivery sheath assembly, the stability tube including a proximal region and a distal region, the distal region including a tubular wall having a plurality of cuts formed through a thickness thereof and configured to be radially expandable from a first shape having a first diameter to a second shape having a second diameter, the second diameter being greater than the first diameter; and

a handle including a housing maintaining the inner shaft assembly, the delivery sheath assembly and the stability tube, the handle being operable to selectively move the delivery sheath assembly relative to the inner shaft assembly and the stability tube;

wherein the delivery device is configured to provide a first delivery state in which the distal region is proximal the capsule and in the first shape, and a deployed state in which the capsule is at least partially withdrawn into the distal region and the distal region is in the second shape.

2. The delivery device of claim 1, wherein an outer diameter of the capsule is greater than an outer diameter of the shaft, and further wherein an inner diameter of the distal region in the first shape approximates the outer diameter of the shaft.

3. The delivery device of claim 2, wherein the outer diameter of the distal region in the first shape is not greater than the outer diameter of the capsule.

4. The delivery device of claim 2, wherein the inner diameter of the distal region in the second shape approximates the outer diameter of the capsule.

5. The delivery device of claim 1, wherein the distal region is configured to self-maintain the second shape upon transitioning from the first shape, and further wherein the delivery device is configured to provide a second delivery state in which the distal region is proximal the capsule and in the second shape, the second shape being sized to receive the capsule.

6. The delivery device of claim 5, wherein the delivery device is configured to transition from the first delivery state to the second delivery state by:

advancing the stability tube relative to the delivery sheath assembly such that the distal region is coaxially disposed over the capsule; and

subsequently retracting the stability tube relative to the delivery sheath assembly such that the distal region is proximal the capsule;

wherein an interface of the distal region with the capsule causes the distal region to transition to the second shape, the distal region maintaining the second shape when retracted from the capsule.

7. The delivery device of claim 5, wherein the handle is further configured to be operable to selectively move the stability tube relative to the delivery sheath assembly and the inner shaft assembly.

8. The delivery device of claim 1, wherein each of the plurality of cuts are longitudinally elongated.

9. The delivery device of claim 8, wherein the plurality of cuts expand in circumferential width in transitioning from the first shape to the second shape.

10. The delivery device of claim 1, wherein the plurality of cuts includes a distal-most cut and a proximal-most cut, and further wherein a longitudinal distance between the distal-most cut and the proximal-most cut is greater than a longitudinal length of the capsule.

11. The delivery device of claim 1, wherein the plurality of cuts are arranged in a pattern about a circumference of the distal region.

12. The delivery device of claim 1, wherein the distal region and the proximal region are defined by a single, homogenous tube.

13. The delivery device of claim 12, wherein a column strength of the distal region and a column strength of the proximal region are substantially equal.

14. The delivery device of claim 12, wherein the homogenous tube is a polymer tube.

15. A system for restoring a defective heart valve of a patient, the system comprising:

a prosthetic heart valve including a stent frame and a valve structure attached to the frame and forming at least two valve leaflets, the prosthetic heart valve being radially self-expandable from a compressed arrangement to a normal, expanded arrangement; and

a delivery device comprising;

an inner shaft assembly including a coupling structure configured to selectively engage the prosthetic heart valve,

a delivery sheath assembly slidably disposed over the inner shaft assembly and including a distal capsule and a proximal shaft, wherein the capsule is configured to compressively contain the prosthetic heart valve in the compressed arrangement,

an outer stability tube slidably disposed over the delivery sheath assembly, the stability tube including a proximal region and a distal region including a tubular wall having a plurality of cuts formed through a thickness thereof and configured to be radially expandable from a first shape having a first diameter to a second shape having a second diameter, the second diameter being greater than the first diameter,

a handle including a housing maintaining the inner shaft assembly, the delivery sheath assembly and the stability tube, the handle being operable to selectively move the delivery sheath assembly relative to the inner shaft assembly and the stability tube;

wherein the system is configured to provide a delivery condition in which the capsule compressively contains the prosthetic heart valve in the compressed arrangement over the inner shaft assembly, and a deployed condition in which the capsule is retracted from the prosthetic heart valve and at least partially into the distal region to permit the prosthetic heart valve to self-deploy toward the normal arrangement and release from the delivery device.

16. The system of claim 15, wherein an outer diameter of the capsule is greater than an outer diameter of the shaft, and further wherein an inner diameter of the distal region in the first shape approximates the outer diameter of the shaft.

17. The system of claim 15, wherein the inner diameter of the distal region in the second shape is not greater than the outer diameter of the capsule.

18. The system of claim 15, wherein the delivery device is configured to provide first and second states in the delivery condition, the first state including the distal region being proximate the capsule and in the first shape, and the second delivery state including the distal region being proximate the capsule and in the second shape.

19. The system of claim 18, wherein the delivery device is configured to transition from the first state to the second state by:

advancing the stability tube relative to the delivery sheath assembly such that the distal region is coaxially disposed over the capsule; and

subsequently retracting the stability tube relative to the delivery sheath assembly such that the distal region is proximal the capsule;

wherein an interface of the distal region with the capsule causes the distal region to transition to the second shape, the distal region configured to self-maintain the second shape when retracted from the capsule.

20. The system of claim 15, wherein the plurality of cuts includes a distal-most cut and a proximal-most cut, and further wherein a longitudinal distance between the distal-most cut and the proximal-most cut is greater than a longitudinal length of the prosthetic heart valve in the compressed arrangement.

21. The system of claim 15, wherein the distal region and the proximal region are defined by a single, homogenous tube.

22. A method of restoring a defective heart valve of a patient, the method comprising:

receiving a delivery device loaded with a radially self-expandable prosthetic heart valve having a stent frame to which a valve structure is attached, the delivery device including a delivery sheath having a capsule extending distally from a shaft and containing the prosthetic heart valve in a compressed arrangement in a delivery state of the delivery device, the delivery device further including an outer stability tube coaxially received over the delivery sheath, the stability tube including a distal region including a tubular wall having a plurality of cuts formed through a thickness thereof and terminating at a distal end located proximal the capsule and defining a first shape having a first diameter;

delivering the prosthetic heart valve in the compressed arrangement through a bodily lumen of the patient to an implantation site of the defective heart valve via the delivery device in the delivery state; and

proximally retracting the capsule from over the prosthetic heart valve and at least partially into the distal region such that the prosthetic heart valve self-deploys from the delivery device and implants within the defective heart valve, the distal region assuming a second shape having a second diameter greater than the first diameter for receiving the capsule.

23. The method of claim 22, wherein prior to the step of proximally retracting the capsule, the method further comprises:

distally advancing the distal region over the capsule such that the capsule exerts an internal expansive force upon the distal region to cause the distal region to transition to the second shape; and

proximally retracting the distal region from the capsule;

wherein the distal region self-maintains the second shape upon retraction from the capsule.

24. The method of claim 23, wherein distally advancing the distal region over the capsule includes the plurality of cuts increasing in circumferential width.

25. The method of claim 23, wherein prior to the step of distally advancing the distal region over the capsule, an inner diameter of the distal region is less than an outer diameter of the capsule in the delivery state.

26. The method of claim 25, wherein prior to the step of distally advancing the distal region over the capsule, the inner diameter of the distal region approximates an outer diameter of the proximal shaft.

27. The method of claim 25, wherein following the step of proximally retracting the distal region from the capsule, the outer diameter of the distal region approximates the outer diameter of the capsule in the delivery state.

28. The method of claim 22, wherein delivering the prosthetic heart valve to an implantation site includes:

establishing an access portal to the bodily lumen of the patient with an introducer device including an introducer sheath and a valve; and

inserting the prosthetic heart valve into the bodily lumen through the introducer valve, including hemostasis being established between the introducer valve and the stability tube.

29. The method of claim 28, wherein proximally retracting the capsule includes the stability tube isolating the delivery sheath from the introducer valve.