[Aortic valve replacement with Medtronic Hall valve (#21) using technique of enlargement of aortic annulus].

Aortic valve replacement was performed in 2 patients with severe aortic stenosis. They showed severe calcified valve and narrow aortic annulus. The aortic annulus was enlarged to 22 mm and 23 mm in diameter in each patient by the technique of Nicks. Then aortic valve replacement was performed with Medtronic-Hall valve (#21) which is supposed to get larger valve area than Björk-Shiley valve. They had good operative course except a complication of complete AV block in the first patient. In this patient a DDD pacemaker was implanted 19 days after operation. Cardiac catheterization was performed 11 or 12 months after operation and good hemodynamics was obtained in both patients. The aortic mean pressure gradient was 6 and 5 mmHg at rest, and 9 and 13 mmHg during exercise on bicycle ergometer in each patient. The aortic valve area was 1.7 and 1.9 cm2, respectively. Body surface area in these patients was 1.29 and 1.36 m2. We concluded that in the small patients we could get a good result with Medtronic Hall valve (#21).