Outcome After Aortic Valve Replacement for Low-Flow/Low-Gradient Aortic Stenosis Without Contractile Reserve on Dobutamine Stress Echocardiography

Objectives This study investigated whether aortic valve replacement (AVR) is associated with improved survival in patients with severe low-flow/low-gradient aortic stenosis (LF/LGAS) without contractile reserve (CR) on dobutamine stress echocardiography (DSE). Background Patients with LF/LGAS without CR have a high mortality rate with conservative therapy. The benefit of AVR in this subset of patients remains controversial. Methods Eighty-one consecutive patients with symptomatic calcified LF/LGAS (valve area = 20% compared with the baseline value. Multivariable analysis and propensity scores were used to compare survival according to whether or not AVR was performed (n = 55). Results Five-year survival was higher in AVR patients compared with medically managed patients (54 +/- 7% vs. 13 +/- 7%, p = 0.001) despite a high operative mortality of 22% (n = 12). An AVR was independently associated with lower 5-year mortality (adjusted hazard ratio from 0.16 to 5.21 varying with time [95% confidence interval: 0.12-3.16 to 0.21-8.50], p = 0.00026). In 42 propensity-matched patients, 5-year survival was markedly improved by AVR (65 +/- 11% vs. 11 +/- 7%, p = 0.019). Associated bypass surgery (p = 0.007) and MPG