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

Abstract

Background: Calcific aortic stenosis (AS) is a progressive disease, and once moderate AS is present, the likelihood of symptom onset within 5 years 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. Methods: 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 ASrelated cardiovascular events was recorded. Results: The mean age was 71 6 10 years, and 63% were men. The mean aortic valve gradient was 30 6 11 mm Hg, and the mean aortic valve area was 0.98 6 0.21 cm 2. Resting GLS and BLS were À16.5 6 4% and À16.9 6 3.6%, respectively. Exercise stress test results were positive in 27 patients (36%). Mean exercise GLS was À17.8 6 3.5%, and mean exercise BLS was À17.9 6 4%. During mean follow-up of 34.5 6 3.5 months, 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. Conclusions: 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.

Impact of transcatheter aortic valve implantation on mechanical dispersion

“…The pressure overload in aortic stenosis (AS) leads to cardiac remodelling, myocardial fibrosis and ultimately impaired myocardial performance 1. While left ventricular (LV) ejection fraction (EF) remains preserved until later stages of the disease, the reliability and prognostic value of global longitudinal strain (GLS) suggests that GLS may be a better marker of early systolic dysfunction in AS phenotypes with small cavity size and increased LV mass 1–4. Moreover, by studying the time course of segmental strain, subtle ventricular heterogeneity can be assessed by mechanical dispersion, which has been previously associated with adverse outcome, mainly ventricular arrhythmias, across a wide range of cardiac conditions 5–10…”

Exercise test in patients with asymptomatic aortic stenosis – clinically useful or not?

“…Although additional technics like the echocardiographic assessment of LV function, cardiopulmonary test, risk score (CURRENT-AS), and biomarkers might improve diagnostic, their role in AAS management requires further investigation to justify a class I indication for surgery instead of classic ET [31][32][33][34][35][36][37][38][39].…”

Challenges and opportunities in improving left ventricular remodelling and clinical outcome following surgical and trans-catheter aortic valve replacement

“…The reduction in LV systolic global longitudinal strain (LGS) measured by echocardiography also predicts the degree of myocardial fibrosis and poorer regression of LVH after SAVR [73]. The reduction in LV basal longitudinal strain also predicts a worse MVO2 on exercise in asymptomatic moderate to severe AS patients and their cardiovascular events [74,75]. Most recently, in moderate aortic stenosis, a reduced LV global longitudinal systolic strain also predicts a higher all-cause mortality and incidence of SAVR during 6-year follow-up [76].…”