The O'Brien-Angell stentless porcine valve: early results with 150 implants.

From August 1991 to June 1994, 150 patients underwent aortic valve replacement with the O'Brien-Angell stentless porcine xenograft (Bravo Cardiovascular Model 300, Cryolife, Atlanta, GA). To establish trends we analyzed three consecutive groups of 50 patients. We found significant differences in low postoperative gradients (mean < or = 10 mm Hg): 24% in group 1, 42% in group 2, and 96% in group 3. Comparing groups 1 and 3, gradients were significantly lower in all valve sizes. The difference is credited to better supraannular positioning of the valve, which is the key to the learning curve. Trivial central regurgitation was present in the three groups at 6%, 12%, and 0%, respectively. Peripheral regurgitation was trivial in 6%, 8%, and 0%, and mild to moderate in 4%, 2% and 0%, respectively. Seventy-eight of 107 patients with an available follow-up exceeding 1 year had noninvasive controls. Two early cases with moderate perivalvular leaks evolved to moderately severe leaks. Two valves were explanted. The O'Brien-Angell stentless valve is easy to handle and correct supraannular positioning provides excellent hemodynamic results.

The O'Brien-Angell stentless valve. Early results of 100 implants.

From August 1991 to May 1993, 100 unselected consecutive patients in whom an aortic bioprosthesis was indicated underwent aortic valve replacement with the O'Brien-Angell stentless porcine xenograft (Bravo Cardiovascular Model 300). The indication was calcified aortic stenosis (AS) in 62 cases (isolated in 44, with associated cardiac lesions in 18), aortic insufficiency in 24 cases (isolated in 13 with associated cardiac lesions in 11), and redo operations in 14 cases. Forty-four percent of the patients were over 70 years of age. With the recommended supra-annular single running suture technique, the aortic cross-clamp times in isolated procedures ranged from 32 to 70 min, mean 39 min. Valve function was studied by echocardiography in 92 patients. Early post-operative transvalvular gradients were usually in the low range, below 15 mmHg in 68% of the cases. Isolated central valvular regurgitation was absent in 60.8%, "microscopic to trivial in 31.5% and mild to moderate in 1.2%. Perivalvular regurgitation was absent in 65.2%, microscopic 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 controls. Transvalvular gradients showed a 30 to 40% reduction when compared to the immediate postoperative values. There were no new isolated central regurgitations but in two cases previously mild-to-moderate perivalvular leaks evolved to moderately severe leaks. Two valves were explanted, one for rupture of a Prolene 4/0 and one due to a slack Prolene 4/0 suture. We consider that the O'Brien-Angell stentless valve was easy to handle in all situations encountered.(ABSTRACT TRUNCATED AT 250 WORDS)