Between January 1983 and October 1990, 20 patients age 80 years or older (mean 82 +/- 1.5 year, range 80 to 87 years) underwent valvular surgery at Clinic for Cardiovascular Surgery Zurich. The indication for operation was aortic stenosis in 19 patients, and mitral insufficiency after previous mitral valve replacement with a bioprosthesis in one. There were 15 elective operations, 2 urgent, and 3 emergency operations. Four of these patients had aortic valve replacement plus coronary artery bypass grafting. The operative mortality rate was 15% (3 patients). All patients were preoperative in NYHA classes III and IV. All survivors remained in NYHA classes I or II. The survivors have been followed from 6 to 70 months (mean 20 +/- 8 months). The actuarial survival rate at 1 and 5 years was 78.5% and 67%, respectively. Valvular replacement can be performed with increased but acceptable mortality and morbidity. Long-term results are encouraging.