Minimally invasive valve replacement system

• US 20060259137A1
• Filed: 07/17/2006
• Published: 11/16/2006
• Est. Priority Date: 10/06/2003
• Status: Abandoned Application

• Current Assignee: Medtronic 3F Therapeutics, Inc. (Medtronic Plc)
• Original Assignee: Medtronic 3F Therapeutics, Inc. (Medtronic Plc)
• Inventors: Myers, Keith E., Artof, Jason, Nguyen, Tuoc Tan
• Application Number:
  US11/489,663
• Publication Number:
  US 20060259137A1
• Time in Patent Office: Days
• US Class Current: 623/2.180
• CPC Class Codes: A61B 5/0066 Optical coherence imaging
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: A61B 5/0086 using infrared radiation
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61B 8/445 Details of catheter construction
• CPC Class Codes: A61F 2/2415 Manufacturing methods
• CPC Class Codes: A61F 2/2418 Scaffolds therefor, e.g. support stents
• CPC Class Codes: A61F 2/243 Deployment by mechanical expansion
• CPC Class Codes: A61F 2/2433 using balloon catheter
• CPC Class Codes: A61F 2/2439 Expansion controlled by filaments
• 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 2220/005 using adhesives
• CPC Class Codes: A61F 2230/0054 V-shaped

Abstract

Methods and systems for minimally invasive replacement of a valve. The system includes a collapsible valve and anchoring structure. The valve assembly comprises a valve and anchoring structure for the valve, dimensioned to fit substantially within the valve sinus.

Claims

1. A foldable, stented valve replacement comprising:

a valve replacement capable of being folded so as to temporarily reduce its diameter by up to 50%; and

a foldable stent positioned about the exterior of the valve, the foldable stent having a circular inflow rim and a circular outflow rim connected by a plurality of longitudinal support posts, the foldable stent being constructed of an elastic material that when folded, will unfold back to its substantially original shape and configuration.

2. The foldable, stented valve of claim 1 wherein the inflow and outflow rims are oval.

3. The foldable, stented valve of claim 1 wherein the stent has three parallel support posts attached to the circular inflow and outflow rims at about 120°

intervals.

4. The foldable, stented valve of claim 1 wherein the stent has three parallel support posts attached to the circular inflow and outflow rims at intervals of about 135°

, 105°

, and 120°

.

5. The foldable, stented valve of claim 1 wherein the stent has three parallel support posts attached to the circular inflow and outflow rims at intervals of about 122°

, 118°

, and 120°

.

6. A foldable, stented valve replacement comprising:

a valve replacement capable of being folded so as to temporarily reduce its diameter by up to 50%; and

a foldable stent positioned about the exterior of the valve, the foldable stent having a circular inflow rim and a circular outflow rim connected by a plurality of longitudinal support posts, the foldable stent being constructed of a memory shaped alloy capable of changing from a malleable martensite phase to a memorized austentite phase at an A_f temperature between about 0°

C. and about 30°

C. such that the stent is capable of being folded in the martensite phase so as to temporarily reduce its diameter by up to 50%.

7. The foldable, stented valve of claim 6 wherein the stent A_f temperature is between about 15°

C. and about 25°

C.

8. The foldable, stented valve of claim 6 wherein the stent is made of Nitinol.

9. The foldable, stented valve of claim 6 whose Nickel content is between about 50% and 60%.

10. A method of manufacturing a Nitinol stent for a heart valve comprising:

expanding Nitinol stock to the desired diameter on a mandrel without increasing the strain in the Nitinol material by more than 15%;

cutting the Nitinol stent with a laser to the desired shape, either before or after the expanding step; and

heat treating the Nitinol stent after the expanding step in order to reduce the strain in the Nitinol material.

11. The method of manufacturing of claim 10 where the strain produced in the expanding step is less than about 8%.

12. A heart valve replacement comprising:

an anchoring structure being constructed of Nitinol, the anchoring structure maintaining a malleable martensite phase at 0°

C., an anchoring structure whose shape and configuration can be transformed in the martensite phase, an anchoring structure whose A_f temperature is between about 15°

C. and about 25°

C., and an anchoring structure capable of returning to its substantially original shape and configuration when exposed to body temperature and implanted into the body.