The Association Between Longitudinal Strain at Rest and Stress and Outcome in Asymptomatic Patients With Moderate and Severe Aortic Stenosis

Abstract

Calcific aortic stenosis (AS) is a progressive disease, and once moderate AS is present, the likelihood of symptom onset within 5years is significant. The aim of this study was to determine the incremental value of global longitudinal strain (GLS) and basal longitudinal strain (BLS) at rest and during exercise on outcomes among asymptomatic patients' with moderate and severe AS. Seventy-five patients with isolated, asymptomatic AS and preserved left ventricular function were retrospectively enrolled and underwent symptom-limited exercise echocardiography. Clinical and echocardiographic data, including GLS and BLS at rest and during exercise, were assessed. Occurrence of AS-related cardiovascular events was recorded. The mean age was 71±10years, and 63% were men. The mean aortic valve gradient was 30±11mm Hg, and the mean aortic valve area was 0.98±0.21cm2. Resting GLS and BLS were -16.5±4% and -16.9±3.6%, respectively. Exercise stress test results were positive in 27 patients (36%). Mean exercise GLS was -17.8±3.5%, and mean exercise BLS was -17.9±4%. During mean follow-up of 34.5±3.5months, cardiovascular events were observed in 45 patients. In multivariate analysis, aortic valve mean gradient (HR, 1.073; 95% CI, 1.032-1.115; P < .001) and peak exercise BLS (HR, 1.177; 95% CI, 1.07-1.295; P = .001) were associated with cardiac events during follow-up. Reduced exercise BLS is associated with future cardiovascular events in patients' with asymptomatic AS, independently of clinical factors and conventional echocardiographic parameters. Detection of postexercise myocardial dysfunction in patients with asymptomatic AS with preserved left ventricular function can aid in risk assessment of these patients.