Treatment decision in asymptomatic aortic valve stenosis: role of exercise testing

Objective-To determine the prognostic value of exercise testing, valve area, and maximum transaortic pressure gradient in asymptomatic patients with aortic valve stenosis. Setting-The outpatient service of a tertiary referral centre for cardiology. Design-Prospective clinical study. Patients-66 consecutive patients with isolated severe aortic stenosis (aortic valve area less than or equal to 1.0 cm(2)) were selected over a 58 month period. Mean (SD) follow up was 14.77 (11.93) months. Interventions-At the initial visit Doppler echocardiography and exercise testing were performed to evaluate ST segment depression and the development of symptoms of aortic stenosis, ventricular arrhythmia, or inadequate rise of systolic blood pressure during exercise. Follow up clinical examinations were performed every three months thereafter to record the onset of symptoms. Main outcome measures-Sudden death or the development of symptoms. Results-Eight patients developed dizziness during exercise testing but made a rapid and spontaneous recovery. No other complications of exercise testing occurred. Survival curves, with or without the occurrence of end point events for the variables studied, showed significant differences for positive versus negative exercise testing (p = 0.0001) and aortic valve area < 0.7 cm(2) upsilon greater than or equal to 0.7 cm(2) (p = 0.0021). There was no relation between the end points and transaortic gradient (p = 0.6882). In multivariate analysis, a hazard ratio of 7.43 was calculated for patients with a positive versus a negative exercise stress test. Although asymptomatic in daily life, 6% of the patients (4/66) experienced sudden death; all these had a positive exercise test and an aortic valve area of less than or equal to 0.6 cm(2). Conclusions-Exercise testing is safe and is of prognostic value in asymptomatic patients with aortic stenosis.