Association of Decreased Right Ventricular Strain with Worse Survival in Non-Acute Coronary Syndrome Angina

Background: Regional strain by speckle-tracking echocardiography can be used to detect occult right ventricular (RV) myocardial dysfunction. However, in patients with coronary artery disease, the impact of RV strain is unknown. The aim of this study was to validate the prognostic value of RV strain in patients with non-acute coronary syndrome angina. Methods: In total, 208 patients with coronary artery disease proved by coronary angiography were retrospectively identified (mean age, 63.81 +/- 10.12 years; 161 men). In addition to clinical and traditional echocardiographic parameters, RV free wall longitudinal strain (RVLS_FW) was measured using speckle-tracking echocardiography from the apical four-chamber view. Cardiac mortality and major cardiovascular events were recorded. Results: During follow-up (23.1 +/- 6.6 months), 27 patients (12.98%) died of cardiovascular causes. These patients were found to have lower left ventricular ejection fractions and greater reductions in the amplitudes of left ventricular peak systolic global longitudinal strain and RVLS_FW. Using -18% as a cutoff point for RV strain, patients with strain <= -18% had superior outcomes (log-rank chi(2) = 9.04 and 6.94 for cardiovascular mortality and arrhythmia, respectively, P = .003). In Cox multivariate regression analysis, RVLS_FW was an independent prognostic factor for both cardiovascular mortality (hazard ratio, 1.27; 95% CI, 1.03-1.72; P = .01) and hemodynamically unstable ventricular arrhythmia (hazard ratio, 1.72; 95% CI, 1.08-2.41; P = .01). Conclusions: RVLS_FW is significantly related to cardiovascular outcomes and hemodynamically unstable ventricular arrhythmia in patients with non-acute coronary syndrome angina.