THE NATURAL-HISTORY OF ADULTS WITH ASYMPTOMATIC, HEMODYNAMICALLY SIGNIFICANT AORTIC-STENOSIS

The natural history of asymptomatic, hemodynamically significant, valvular aortic stenosis in adults was documented. Of 471 patients with aortic stenosis identified by Doppler echocardiography (peak systolic flow velocity ≥4 m/s) from January 1994 through August 1987, 143 were asymptomatic and had isolated valvular aortic stenosis. Thirty patients underwent aortic valve intervention within 3 months (group 1); the remaining 113 patients did not have an intervention within 3 months (group 2). Follow-up information was available for all patients; the mean duration of follow-up study was 20 months (range 6 to 48). Three cardiac events occurred in the 30 group 1 patients after operation (two deaths, one reoperation). Among the 113 group 2 patients, three had cardiac death presumed to be a result of the aortic stenosis; all three developed symptoms at least 3 months before death. The actuarial probability of remaining free of symptoms of angina, dyspnea or syncope for group 2 was 86% at 1 year and 62% at 2 years. For this group, the 1 and 2 year probabilities of remaining free of cardiac events, including aortic valve intervention or cardiac death, were 93% and 74%, respectively. Of all clinical and echocardiographic variables (group 2), only Doppler flow velocity (p = 0.004) and ejection fraction (p = 0.01) were independent predictors of subsequent cardiac events. Among the 44 patients (groups 1 and 2) with a flow velocity ≥4.5 m/s, the relative risk of sustaining a cardiac event (by Cox regression analysis) was 4.9 (p = 0.004). Patients with asymptomatic, hemodynamically significant aortic stenosis are at significant risk for cardiac events within 2 years. However, during the time they remain asymptomatic, the risk of sudden death is low. The asymptomatic patient may be treated medically but requires careful follow-up evaluation for the development of symptoms. © 1990.