Detection of Left Ventricular Dysfunction by Global Longitudinal Systolic Strain in Patients with Chronic Aortic Regurgitation

Abstract

The purpose of this study was to investigate whether global longitudinal strain measured by two-dimensional speckle tracking echocardiography could detect incipient myocardial dysfunction in patients with chronic aortic regurgitation (AR). Disclosing left ventricular (LV) dysfunction is of decisive importance for optimal timing of surgery but challenging because of the altered loading conditions. Forty-seven patients referred for aortic valve replacement because of chronic AR were studied, along with 31 healthy controls. Myocardial deformation as determined by longitudinal, circumferential, and radial strain was calculated using two-dimensional speckle-tracking echocardiography technique, in addition to LV volumes, dimensions, and ejection fraction. Strain values were normalized to end-diastolic volume to correct for the volume dependency of deformation. Global systolic longitudinal strain was significantly lower in patients with AR before surgery compared with the healthy controls (-17.5 ± 3.1% vs -22.1 ± 1.8%, P < .01), while global circumferential strain and LV ejection fraction did not differ (-21.7 ± 3.4% vs -22.6 ± 2.5%, P= .22 and 59 ± 5% vs 59 ± 6%, P= .59, respectively). However, differences between patients and controls were evident for both longitudinal and circumferential strain when normalized to end-diastolic volume (-0.09 ± 0.04 vs -0.23 ± 0.08, P < .01, and -0.11 ± 0.05 vs -0.24 ± 0.08, P < .01, respectively). In contrast to their absolute values, both normalized variables demonstrated improvement in myocardial shortening after valve replacement (P < .01). The study demonstrated reduced global longitudinal strain in patients with chronic AR with preserved LV ejection fractions. Global longitudinal strain might therefore disclose incipient myocardial dysfunction with a consequent potential for improved timing of aortic valve surgery.