Valvuloplasty devices and methods
The present invention provides an aortic valvuloplasty catheter which, in one preferred embodiment, has a tapered distal balloon segment that anchors within the left ventricle outflow track of the patient's heart and a rounded proximal segment which conforms to the aortic sinuses forcing the valve leaflets open. In addition, this embodiment of the valvuloplasty catheter includes a fiber-based balloon membrane, a distal pigtail end hole catheter tip, and a catheter sheath.
1. A method of performing aortic valvuloplasty comprising:
providing a catheter having a balloon;
advancing said catheter towards an aortic valve;
expanding a first region of said balloon to a first maximum inflated diameter so as to contact a patient's ventricular outflow tract to reduce downstream migration of said balloon;
expanding a second region of said balloon to a second maximum inflated diameter so as to hyperextend a patient's valve leaflets against an aortic sinus; and,
expanding a third region of said balloon to a third maximum inflated diameter that is smaller than said first and second maximum inflation diameter and substantially equal to a diameter of a patient's valve annulus so as to prevent dissection of said annulus;
wherein said third region is located between said first region and said second region.
2. The method as set forth in claim 1 , wherein said first region expands at a first media pressure and said second region expands at a second media pressure.
3. The method as set forth in claim 1 , wherein said first region has a first compliancy, said second region has a second compliancy and said third region has a third compliancy.
4. The method as set forth in claim 3 , wherein said first region expands prior to expansion by said second region.
5. The method as set forth in claim 1 , further comprising, allowing perfusion of blood past said expandable member.
6. The method as set forth in claim 1 , further comprising measuring a pressure proximal and distal to said aortic valve.
7. The method as set forth in claim 1 , further comprising depositing an anti-restenosis agent in a region of said aortic valve.
8. The method according to claim 1 , further comprising:
providing a sheath movable over said catheter such that movement of said sheath controls exposure of said balloon; and,
stabilizing said balloon with said sheath after expanding said balloon.
9. The method of claim 1 , wherein said first and second media pressures are substantially equal.
10. A method of treating a heart valve comprising:
identifying a target heart valve having diseased leaflets;
delivering a balloon an at said diseased leaflets; and,
expanding a first region of said balloon to a first maximum inflated diameter so as to engage a patient's ventricular outflow tract to reduce downstream migration of said balloon;
expanding a second region of said balloon to a second maximum inflated diameter so as to hyperextend a patient's valve leaflets against an aortic sinus; and,
expanding a third region of said balloon to a third maximum inflated diameter that is smaller than said first maximum inflated diameter and second maximum inflated diameter and not greater than a diameter of a patient's valve annulus so as to prevent distension of said annulus
wherein said third region is located between said first region and said second region.
11. A method according to claim 10 , wherein said first region expands at a first media pressure and said second region expands at a second media pressure.
12. A method according to claim 11 , wherein said first region has a first compliancy, said second region has a second compliancy and said third region has a third compliancy.
13. A method according to claim 11 , wherein said first region is shared to conform to a share of said ventricular outflow tract when expanded to said first maximum inflated diameter.