From September 1986 to September 1987 percutaneous balloon valvuloplasty was performed in 20 patients with critical aortic stenosis. The mean age was 74, range 54 to 90 years. Two patients were NYHA class II, 10 patients were functional class III and eight were class IV. After percutaneous balloon valvuloplasty, using 15, 18 or 20 mm diameter balloon catheters via a 14F vascular sheath from the femoral artery, one patient was class I, 11 class II and seven were class III. One patient, who had only minimal reduction of aortic valve gradient from 120 to 100 mmHg, remained in class IV. The systolic gradient was reduced by 50% from 70 +/- 26 (+/- SD) to 35 +/- 22 mmHg (P less than 0.001) after valvuloplasty and the aortic valve area increased by 43% from 0.51 +/- 0.12 to 0.73 +/- 0.25 cm2 (P less than 0.001). There were no procedural or 30 day deaths nor any embolic events. Percutaneous balloon valvuloplasty is a relatively safe and effective treatment for the older adult with symptomatic aortic stenosis.