Left Ventricular Remodeling and Its Progression in Asymptomatic Patients with Chronic Aortic Regurgitation: Evaluation by Speckle-Tracking Echocardiography

Abstract

Background: Progression of chronic aortic regurgitation (CAR) is insidious, and management is challenging. The primary aim of this study was to evaluate left ventricular (LV) remodeling and its progression in asymptomatic patients with CAR and preserved LV ejection fraction by three-dimensional speckle-tracking echocardiography (STE). The secondary aim was to identify the effect of management strategies on LV remodeling in severe CAR.

Methods: One hundred thirty-five patients and 41 control subjects were enrolled. Patients were divided according to regurgitation degree: mild (n = 48), moderate (n = 40), or severe (n = 47). Routine follow-up was not possible in 13 patients in the severe CAR group. The remaining 34 patients were divided into three groups on the basis of treatment (surgical, n = 13; drug, n = 11; and untreated, n = 10) and followed for 2.1 ± 0.37 years. All subjects underwent three-dimensional STE at baseline and follow-up, while 20 patients with CAR also underwent baseline two-dimensional STE and feature-tracking cardiovascular magnetic resonance imaging. Volumetric and strain parameters were acquired.

Results: Compared with global circumferential strain derived from two-dimensional STE and feature-tracking cardiovascular magnetic resonance imaging, three-dimensional global circumferential strain was largest (P < .001); however, no significant differences in volumetric parameters, global longitudinal strain (GLS), and global radial strain (GRS) were identified at baseline. GLS, GRS, torsion, apical rotation, and twist were worse in the severe group (P < .05). During follow-up, LV volumetric indexes and sphericity indexes increased, while global longitudinal strain, apical rotation, and twist worsened (P < .05) in the untreated group. In the surgical group, LV volumetric and sphericity indexes decreased, while GLS and GRS improved (P < .05). In the drug group, LV volumetric indexes increased, while LV ejection fraction, GLS, and GRS worsened (P < .05).

Conclusions: Three-dimensional STE may be a reliable tool to monitor the progression of ventricular remodeling in CAR. Drug therapy may not prevent progressive ventricular dilatation and myocardial depression.

Keywords: Aortic valve replacement; Chronic aortic regurgitation; Left ventricular remodeling; Myocardial strain; Speckle-tracking echocardiography.