Background. A wealth of data exists on acceptable mortality and morbidity for valve operations in older patients, yet information documenting quality of life is lacking. Methods. From October 1974 to May 1998, 2,075 patients aged 65 years and older underwent valve replacement using a porcine bioprosthesis. There were 1,126 men (54.3%) and 949 women (45.7%) with a mean age of 73.9 years (range 65 to 104 years). Results. The elective hospital mortality was 8.5% (158 patients), and urgent/emergent/salvage mortality was 25.8% (54 patients). Fellow-up was completed for 1,863 patients (98.2%) and extended from 1 month to 23.0 years (mean 60.8 months) with cumulative follow-up of 9,442.1 patient-years. At follow-up, surviving patients (n = 849) completed the Short Form-36 Quality of Life Survey. Results showed patients had a more favorable quality of life compared with control subjects matched for age and sex. Functional improvement was significant with 96.3% in New York Heart Association functional class I or II at follow-up. There were 74 valves that failed from all causes (33 aortic and 41 mitral valves). Actuarial freedom from valve failure at 9 years was 94.4% +/- 1.1% and at 18 years was 83.7% +/- 2.4%. Conclusions. Valve replacement in older patients provides excellent functional improvement, reduces late cardiac events, and enhances quality of life. (C) 2001 by The Society of Thoracic Surgeons.