From August 1977 through August 1984, 239 patients underwent aortic valve replacement (AVR) with the lonescu-Shiley pericardial valve. Isolated AVR was performed in 112 patients and associated cardiac surgery in 127 patients (53.1 %). One hundred twenty-eight patients were males and 111 females, with an average age of 50.6 years (range 15 to 78 years). There were 24 hospital deaths (10%) and 15 late deaths (8.9%). The expected 100 months survival rate was 82.8±5.5 (91.3 ±5.6% for isolated AVR, and 75 ± 7.8% for associated AVR). All patients were postoperatively studied until December 1985. The cumulative duration of follow-up was 894.08 patient-years, with a mean follow-up of 44.9 months per patient. There were 10 thromboembolic episodes in this series (3 peripheral and 7 central), with a linearized incidence of 1.1 % per patient-year. The actuarial projection of freedom from thromboembolic episodes at 100 months follow-up was 94.4 ± 3,4% (96.9 ± 2.2% for isolated AVR, and 92.6 ± 3.9% for associated AVR). Twenty-five patients required reoperation (2.79% per patient-year): 6 for infective endocarditis, 3 for paravalvular leak, one for valve thrombosis, 3 for another valve explantation, and 12 for primary tissue failure (1.3% per patient-year). In conclusion, the lonescu-Shiley valve has a satisfactory performance in the aortic position at long-term follow-up. In our experience, the higher rate of postoperative complications occurred among patients with concomitant cardiac surgery, so not necessarily related to this pericardial valve.