Chronic Mitral Regurgitation: Left Atrial Deformation Analysis by Two-Dimensional Speckle Tracking Echocardiography

Background: Speckle tracking echocardiography (STE) is a novel method for the angle-independent and objective quantification of myocardial deformation; it has recently evolved, enabling the quantification of longitudinal myocardial left atrial (LA) deformation dynamics. To investigate the effects of chronic mitral regurgitation (MR) on these functional atrial indices, we analyzed LA function by STE in a group of asymptomatic patients with chronic degenerative MR. Methods: The study population included 36 patients with mild MR, 38 with moderate MR, and 42 with severe MR. 52 age-matched controls were also recruited. Global peak atrial longitudinal strain (global PALS) was measured in all subjects by averaging all atrial segments. Results: Age, gender, and LV ejection fraction in all pathological groups were comparable to those in the controls. Global PALS was higher in the mild MR group (46.7 +/- 9.1%) in comparison with the controls (40.5 +/- 6.2%; P < 0.001); instead global PALS was lower in the moderate MR group (25.7 +/- 7.1%) and further reduced in the severe MR group (13.2 +/- 5.2%) in comparison with the controls (40.5 +/- 6.2%; overall P < 0.0001 by ANOVA, P < 0.05 for all pairwise comparisons). In multivariate analysis, E/Em ratio emerged as the principal independent determinant of global PALS. Conclusions: Our study provides new insight for the LA function analysis in response to different degrees of MR, showing that STE measurements of LA longitudinal strain may be considered a promising tool for the early detection of impairment of LA compliance in patients with asymptomatic chronic MR. (Echocardiography 2011;28:327-334).