Survival after intervention in patients with low gradient severe aortic stenosis and preserved left ventricular function

Abstract

The outcome of aortic valve replacement for patients with low gradient severe aortic stenosis and preserved ejection fraction has been debated. The aim of the present study was to evaluate the effect of aortic valve intervention on survival in that group. A cohort of 416 consecutive patients with low gradient severe aortic stenosis (aortic valve area, ≤ 1 cm(2); mean pressure gradient, <40 mm Hg) and preserved ejection fraction (≥ 50%) were identified from the Sheba Medical Center echocardiography database. Clinical data, aortic valve intervention, and death were recorded. During an average follow-up of 28 months, of 416 study patients (mean age, 76 ± 14 years, 42% men), 97 (23%) underwent aortic valve intervention and 140 (32%) died. Mantel-Byar analysis showed that the cumulative probability of survival was significantly greater after aortic valve intervention. Multivariate analysis revealed a 49% reduction in the risk of death after surgery (P < .05). The survival benefit of aortic valve intervention was comparable with adjustment to older age, aortic valve area ≤ 0.8 cm(2), and a low (≤ 35 cm(2)/m(2)) or normal (>35 cm(2)/m(2)) stroke volume index. Our findings suggest that aortic valve intervention is associated with improved survival among patients with low gradient severe aortic stenosis and preserved left ventricular function. The presence of either a low or normal stroke volume index did not affect the mortality benefit.