Background: The role of speckle-tracking echocardiography in the assessment of chronic aortic regurgitation (AR) is not established. Load dependency may encumber the interpretation of strain measurements in the chronically overloaded left ventricle. The aim of this study was to investigate the mechanisms of left ventricular (LV) contraction patterns in asymptomatic patients with moderate to severe AR and preserved ejection fractions.
Methods: In this prospective, cross-sectional study, 31 patients with moderate to severe AR, 15 elite endurance athletes, and 17 healthy control subjects were examined using three-dimensional speckle-tracking echocardiography. Global circumferential strain (GCS), global longitudinal strain (GLS), end-systolic circumferential wall stress (ESSc), end-systolic meridional wall stress (ESSm), and the wall stress ratio (ESSc/ESSm) were measured.
Results: LV end-diastolic volumes were similar in athletes and patients with AR and significantly larger than in healthy control subjects. Values of GLS in control subjects, athletes, and patients with AR were -18.8 ± 1.9%, -17.3 ± 2.0%, and -16.4± 2.0%, respectively (control subjects vs athletes and patients, P < .05), whereas values of GCS were -16.9 ± 2.0%, -15.5 ± 1.9%, and -17.9 ± 2.6%, respectively (athletes vs control subjects and patients, P < .01). The ESSc/ESSm ratio was lower in patients with AR (P < .01). When adjusted for ESSm, GLS remained impaired in patients compared with control subjects and athletes (P = .015). On the other hand, GCS was better in patients with AR when adjusted for ESSc (P = .003).
Conclusions: In compensated AR, relatively high GCS compensates for reduced GLS in a manner consistent with the preserved ejection fractions observed in these patients.
Keywords: Aortic regurgitation; Echocardiography; Left ventricular function; Speckle-tracking; Wall stress.
Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.