THE OBRIEN-ANGELL STENTLESS VALVE - EARLY RESULTS OF 100 IMPLANTS

From August 1991 to May 1993, 100 unselected consecutive patients in w hom an aortic bioprosthesis was indicated underwent aortic valve repla cement with the O'Brien-Angell stentless porcine xenograft (Bravo Card iovascular Model 300). The indication was calcified aortic stenosis (A S) in 62 cases (isolated in 44, with associated cardiac lesions in 18) , aortic insufficiency in 24 cases (isolated in 13 with associated car diac lesions in 11), and redo operations in 14 cases. Forty-four perce nt of the patients were over 70 years of age. With the recommended sup ra-annular single running suture technique, the aortic cross-clamp tim es in isolated procedures ranged from 32 to 70 min, mean 39 min. Valve function was studied by echocardiography in 92 patients. Early post-o perative transvalvular gradients were usually in the low range, below 15 mmHg in 68% of the cases. Isolated central valvular regurgitation w as absent in 60.8%, ''microscopic'' to trivial in 31.5% and mild to mo derate in 1.2%. Perivalvular regurgitation was absent in 65.2%, micros copic to trivial in 26.2% and mild to moderate in 3.2%. Thirty-five of 40 patients with follow-ups exceeding 6 months had non-invasive contr ols. Transvalvular gradients showed a 30 to 40% reduction when compare d to the immediate postoperative values. There were no new isolated ce ntral regurgitations but in two cases previously mild-to-moderate peri valvular leaks evolved to moderately severe leaks. Two valves were exp lanted, one for rupture of a Prolene 4/0 and one due to a slack Prolen e 4/0 suture. We consider that the O'Brien-Angell stentless valve was easy to handle in all situations encountered. Prolene 3/0 instead of 4 /0 should avoid the only problems encountered, of perivalvular leaks d ue to slack sutures or late rupture. The good performance of the valve needs to be confirmed by long-term studies.