DEVICES AND METHODS FOR REDUCING VENOUS PRESSURE

• US 20110190874A1
• Filed: 01/28/2011
• Published: 08/04/2011
• Est. Priority Date: 01/29/2010
• Status: Active Grant

• Current Assignee: Corvia Medical, Inc.
• Original Assignee: DC Devices Inc.
• Inventors: Celermajer, David, Sutherland, Michael W., McNamara, Edward
• Granted Patent: US 9,277,995 B2
• Time in Patent Office: Days
• US Class Current: 623/1.26
• 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 2/2475 Venous valves
• CPC Class Codes: A61F 2210/0014 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2220/0008 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2220/0016 with sharp anchoring protrusions, e.g. barbs, pins, spikes
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2250/0029 differing in bending or flexure capacity
• CPC Class Codes: A61F 2250/0036 differing in thickness

Abstract

Devices and method are disclosed for reducing pressure in a patient'"'"'s vena cava and in the right atrium of a patient'"'"'s heart. A valve is implanted in the inferior vena cava (IFC) between the patient'"'"'s renal veins and hepatic veins. When pressure in a patient'"'"'s IFC reaches high levels, i.e., the pressure differential across the valve reaches high levels, the valve automatically closes or begins to close. The closing is caused by the pressure of the patient'"'"'s blood moving one or more flaps in the valve to a closed or near-closed position. This prevents excessive pressure in the upper or superior vena cava and the right atrium of the patient'"'"'s heart. The device also includes a pressure relief feature that opens and allows retrograde flow of blood if the pressure differential exceeds a yet higher pressure.

Claims

1. A device for treating heart failure of a patient, comprising:

a stent for implantation in an inferior vena cava of the patient;

at least one pressure control feature attached to the stent; and

at least one connector joining the at least one pressure control feature to said stent,

wherein the pressure control feature is configured to prevent elevated blood pressure from damaging an organ or vessel.

2. The device of claim 1, wherein the at least one pressure control feature is designed to induce a pressure differential across the device.

3. The device of claim 1, wherein the at least one pressure control feature is design to impede flow of blood in a normal direction in the inferior vena cava.

4. The device of claim 1, wherein the at least one pressure control feature comprises a plurality of flaps which are open to allow blood flow in a normal direction and which are designed to begin to close when a pressure differential across the device is at least 10 mm Hg.

5. The device of claim 1, further comprising a pressure relief feature that allows blood to flow in a retrograde direction when the pressure control feature is activated.

6. The device of claim 1, wherein the connector is selected from the group consisting of a suture and a crimping member.

7. A device for treating heart failure, comprising:

an elongate tubular stent member;

at least one pressure control feature;

at least one pressure relief feature; and

a connector joining said at least one pressure control feature to said elongate tubular member,

wherein the at least one pressure control feature is configured to prevent elevated blood pressure from damaging an organ or a vessel by inducing a pressure differential across the device, and

wherein the pressure relief feature is configured to reduce the pressure differential if the pressure differential exceeds a desired value.

8. The device of claim 7, wherein the at least one pressure control feature comprises at least one flexible flap and wherein the pressure relief feature comprises at least one flexible portion of a wall of the elongate tubular stent member.

9. The device of claim 7, wherein the pressure relief feature comprises a portion of a flexible flap attached to a wall of the elongate tubular stent member.

10. The device of claim 7, wherein the pressure relief feature comprises at least one portion of a wall of the elongate tubular stent member having a reduced cross section or thickness.

11. A device to reduce venous pressure comprising:

a stent adapted to exert an outward radial force upon a lumen of an inferior vena cava;

at least one anchor integral with said stent adapted to contact a surface of said lumen;

a valve having a first side and a second side and configured to allow blood to flow in a first direction, wherein said first direction is a normal direction of blood flow and wherein said normal direction of blood flow is from said first side to said second side, said valve configured to close when a venous pressure on the second side of the valve exceeds a venous pressure on the first side of the valve by a predetermined amount; and

an emergency release feature that allows blood to flow retrograde in a direction opposite to the normal direction while said valve is at least partially closed.

12. The device of claim 11, wherein the valve comprises a plurality of flexible flaps connected to the elongate stent member.

13. The device of claim 11, wherein said valve comprises a biocompatible sheet attached to said stent, said biocompatible sheet having a plurality of slits and flaps allowing blood to flow in a first direction of normal blood flow and impeding blood flow in the first direction when the venous pressure on the second side of the valve exceeds the venous pressure on the first side of the valve by a predetermined amount.

14. A device to reduce venous pressure comprising:

a stent adapted to exert an outward radial force upon a lumen of an inferior vena cava;

a pressure control device attached to said stent, said pressure control device having a first opening and a second opening, said second opening having an area larger than said first opening; and

a biocompatible sheet having a first side and a second side and secured to said pressure control device, said sheet comprising apertures configured to open when venous pressures on the first side and second side of the biocompatible sheet are normal, thereby allowing blood flow in a first direction and for said apertures to close when the venous pressure on the second side exceeds the venous pressure on the first side by a predetermined amount, thereby impeding blood flow in the first direction.

15. The device of claim 14, wherein said first and second openings permit blood flow in a second direction opposite to the first direction when the venous pressure on the second side exceeds the venous pressure on the first side by a predetermined amount.

16. The device of claim 14, wherein said pressure control device has a shape of a frustoconical section with the larger opening intended for deployment nearer a hepatic vein of a patient and a smaller opening intended for deployment nearer a renal vein of a patient.

17. A method of reducing venous pressure, the method comprising:

providing a pressure control device comprising a valve configured to allow blood to flow in a normal direction in an inferior vena cava; and

implanting the pressure control device into a patient'"'"'s inferior vena cava between said patient'"'"'s hepatic veins and renal veins, wherein the pressure control device is configured to close when a venous pressure downstream from the valve exceeds a venous pressure upstream from the valve by a first predetermined amount.

18. The method of claim 17, further comprising providing a pressure relief feature, wherein blood is allowed to flow retrograde to the normal direction when the venous pressure downstream from the valve exceeds the venous pressure upstream from the valve by a second predetermined amount greater than the first predetermined amount.

19. The method of claim 17, wherein the pressure control device closes when the venous pressure downstream from the valve exceeds a venous pressure upstream from the valve by a first predetermined amount by movement of flexible flaps to close at least one opening in the valve.

20. The method of claim 18, wherein the pressure relief feature operates by movement of a flexible outer portion of the pressure control device.