The mitral pulmonary autograft: assessment at midterm.

BACKGROUND: There is a dire need, especially in emergent societies, for a mitral substitute that does not require anticoagulation, and is not affected by early degeneration.

METHODS: Between 1997 and 2003, 80 patients had successful mitral valve replacement with a pulmonary autograft. Fifty-five patients were female, and the mean age was 39.3 years. Seventy-eight patients had rheumatic mitral disease and 2 congenital. The autograft was placed inside a rigid Dacron tubing for support, and the right ventricular outflow was reconstructed with a xenograft or a homograft. Recently we have used microwave energy to ablate atrial fibrillation when present.

RESULTS: Intraoperative transesophageal echocardiography revealed adequate mitral valve areas (mean area 2.76 cm2) and acceptable mitral gradients (mean 4.3 mm Hg) in all 80 patients. There was no mitral regurgitation or trace amounts in 61 patients, and mild regurgitation in 19. Operative mortality was 5.0%, and late mortality clearly related to the procedure 6.25%. Follow-up was complete except for 2 lost patients, with a mean of 25 months, and echocardiographic findings were generally stable during follow-up. One patient developed uncritical mitral stenosis and another uncritical stenosis and insufficiency during 4 to 5.5 years. Four more patients had progression of mitral regurgitation from "mild" to "moderate" over a period from 8 months to 3 years. Uncritical xenograft pulmonic stenosis developed in 2 patients. Most of the surviving patients (83%) remain in class I status.

CONCLUSIONS: We believe the pulmonary autograft is a good mitral substitute at the disposal of cardiac surgeons, especially when patients are young and when life anticoagulation is contraindicated or impractical.