Background .– Low-flow low-gradient aortic stenosis with preserved ejection fraction is a recently described entity, but its prognostic implication has only been little studied.

Methods .– Three hundred and sixty-two patients with severe aortic stenosis, defined by an aortic valve area (AVA) ≤ 0.6 cm ² /m ^é , and LVEF ≥ 50% were prospectively included. We performed 2D-strain imaging to assess LV systolic function. Global afterload was evaluated by valvulo-arterial impedance (Zva). Four groups were defined depending on flow and gradient: low flow was defined as a stroke volume index (SVi) ≤ 35 mL/m ² , and low gradient as a mean gradient (MG) ≤ 40 mmHg.

Results .– Group 1 (normal flow high gradient) represented the majority of our patients (231 patients, 63.5%). Three-year survival was 87%. Referral rate for surgery was 75%. There was a significant improvement of survival among the surgery group (88% vs 75% in the medical group, P = 0.035).

Group 2 (low flow high gradient) represented 46 patients (12.6%). Three-year survival was excellent: 95% ( P = ns vs group 1). Referral rate for surgery was 76%. There was a significant improvement of survival among the surgery group (100% vs 76% in the medical group, P = 0.01).

Group 3 (high flow low gradient) represented 57 patients (15.7%). Three-year survival was good: 85% ( P = ns vs group 1). Referral rate for surgery was 55%. There was a significant improvement of survival among the surgery group (90.6% vs 74.7% in the medical group, P = 0.04).

Group 4 (low flow high gradient) represented 30 patients (8.2%). Three-year survival was the lowest: 64% ( P = 0.04 vs group 2). Referral rate for surgery was 56%. However there was no significant improvement with surgery (3-year survival 61.6% vs 72.7% in the medical group, P = 0.93).

Conclusion .– Low-flow low-gradient aortic stenosis is a rare disease, and its prognosis does not seem to be improved by surgery. However these data need to be confirmed in further studies.