Prosthetic valve delivery system
A prosthetic valve delivery system for percutaneously delivering and deploying a prosthetic valve within an existing valve is disclosed. The delivery system includes a stented prosthetic valve having a balloon-expandable stent portion with a prosthetic valve disposed therein and at least one self-expanding stent portion. The delivery system further includes a dual balloon catheter having a first balloon on which the stented prosthetic valve is disposed during delivery and a second balloon. Upon delivery within the existing valve, the self-expanding stent portion contacts the existing valve and the first balloon expands the balloon-expandable stent portion to a first diameter such that the stented prosthetic valve is in a first stage deployment configuration. The second balloon then expands the balloon-expandable stent portion to a second diameter, greater than the first diameter, such that the stented prosthetic valve is in a second stage deployment configuration being fully deployed within the existing valve.
1. A prosthetic valve delivery system comprising:
a stented prosthetic valve having
a tubular stent assembly with a balloon-expandable stent portion attached to at least one self-expanding stent portion, and
a prosthetic valve component disposed within and secured to the balloon-expandable stent portion of the stent assembly; and
a dual balloon catheter having
a first balloon on which the stented prosthetic valve is disposed in a delivery configuration, the first balloon having a first working diameter for expanding the balloon-expandable stent portion to a first diameter, and
a second balloon having a second working diameter that is greater than the first working diameter of the first balloon for expanding the balloon-expandable stent portion to a second diameter greater than the first diameter.
2. The delivery system of claim 1 further comprising:
an outer tubular sheath defining a lumen in which the dual balloon catheter is slidingly disposed, wherein the outer tubular sheath radially constrains the at least one self-expanding stent portion of the stented prosthetic valve in the delivery configuration.
3. The delivery system of claim 2 , wherein when the outer tubular sheath is proximally retracted relative to the self-expanding stent portion, the self-expanding stent portion deploys into an expanded configuration with the balloon-expandable stent portion of the stented prosthetic valve remaining collapsed on the first balloon in the delivery configuration.
4. The delivery system of claim 3 , wherein expansion of the first balloon expands the balloon-expandable stent portion to the first diameter such that the stented prosthetic valve is in a first stage deployment configuration and released from the dual balloon catheter when the first balloon is deflated.
5. The delivery system of claim 4 , wherein the second balloon is slidable within the balloon-expandable stent portion when the stented prosthetic valve is in the first stage deployment configuration.
6. The delivery system of claim 5 , wherein expansion of the second balloon within the balloon-expandable stent portion expands the balloon-expandable stent portion to the second diameter such that the stented prosthetic valve is in a second stage deployment configuration.
7. The delivery system of claim 6 , wherein in the second stage deployment configuration an outer surface of the balloon-expandable stent portion is brought into apposition with a surface of a treatment site.
8. The delivery system of claim 6 , wherein the first balloon is disposed on the dual balloon catheter proximal of the second balloon.
9. The delivery system of claim 6 , wherein the first balloon is disposed on the dual balloon catheter distal of the second balloon.
10. The delivery system of claim 1 , wherein the balloon-expandable stent portion is attached at each end to a respective self-expanding stent portion.