Results of percutaneous transluminal coronary angioplasty in patients greater than or equal to 65 years of age (from the 1985 to 1986 National Heart, Lung, and Blood Institute's Coronary Angioplasty Registry). The 1985 to 1986 National Heart, Lung, and Blood Institute Percutaneous Transluminal Coronary Angioplasty (PTCA) Registry series of 1,801 initial procedures included 486 patients age greater than or equal to 65 years (elderly). In comparison to younger patients, a greater proportion of elderly patients were women and had unstable angina. Elderly patients had more history of hypertension and more history of congestive heart failure. Although the elderly had more extensive vessel disease, the numbers of lesions and vessels attempted with PTCA were similar in the older and younger cohorts. Angiographic success rates were similar for all age groups. Although complication rates in the catheterization laboratory did not differ, patients greater than or equal to 65 years were much more likely to require emergency coronary artery bypass graft surgery (CABG) (5.4 vs 2.8%, p less than 0.05) or elective CABG (3.9 vs 1.6%, p less than 0.01). The in-hospital death rate was considerably higher among the elderly (3.1 vs 0.2%, p less than 0.01). At 2-year follow-up, symptomatic status and cumulative rates of myocardial infarction, CABG and repeat PTCA were similar for elderly and younger patients. The death rate after 2 years was higher among elderly patients (8.8% of patients greater than or equal to 65 years vs 2.9% of patients less than 65 years, p less than 0.01). When the relative risk of death for the elderly was adjusted for factors more prevalent among those greater than or equal to 65 years (history of congestive heart failure, multivessel disease, unstable angina, history of hypertension and female gender), the relative risk remained significant but was substantially reduced (from 3.3 to 2.4). 