Fifteen years' single-center experience with the ATS bileaflet valve.

BACKGROUND AND AIM OF THE STUDY Since its introduction in May 1992, the bileaflet ATS Open Pivot valve has been implanted routinely at the authors' institution. The study aim was to analyze, retrospectively, the 15-year clinical results of these implanted ATS valves. METHODS Between May 1992 and December 2005, a total of 1,160 ATS valves (749 aortic, 381 mitral, 21 tricuspid, nine pulmonary) was implanted in 1,047 consecutive patients (655 males, 392 females; mean age 62.1 +/- 12.4 years). Preoperatively, 75% of the patients were in NYHA class III or higher (mean 3.1). The most frequent comorbidities included atrial fibrillation (n = 381), coronary disease (n = 288) and diabetes (n = 172). RESULTS The mean follow up was 78 months (range: 24-183 months); the total follow up was 6,887 patient-years (pt-yr) and was 99.8% complete. In-hospital mortality was 4% (n = 43; three valve-related). Survival (Kaplan-Meier) at five and 10 years was significantly better for aortic than for mitral valve patients (84% and 65% versus 75% and 41%, respectively) (Mantel-Cox, p < 0.001). A log rank analysis detected no statistical difference in the incidence of thromboembolism (p = 0.182) or bleeding (p = 0.375) between both groups. The overall linearized incidences were: thromboembolism 1.08%/pt-yr; bleeding 0.91%/pt-yr; endocarditis 0.22%/pt-yr; paravalvular leakage 0.33%/pt-yr; and valve thrombosis 0.21%/pt-yr. Multivariate analysis (Cox regression) indicated age > 70 years (p < 0.0001), NYHA class > or = III (p < 0.0001), non-sinus rhythm (p = 0.001), concomitant CABG (p = 0.008) and higher INR values (p = 0.013) to be significant risk factors for death. CONCLUSION This 15-year experience with the ATS bileaflet prosthesis showed excellent clinical outcomes for patients, with no structural failure and an acceptable incidence of adverse events.