Role of Left Atrial Reservoir Strain Rate in Left Atrial Remodeling in Severe Mitral Regurgitation

Li-Tan Yang; Wei-Chuan Tsai; Chwan-Yau Luo; Yi-Heng Li; Liang-Miin Tsai

doi:10.1016/j.jmu.2016.09.003

Role of Left Atrial Reservoir Strain Rate in Left Atrial Remodeling in Severe Mitral Regurgitation

J Med Ultrasound. 2017 Jan-Mar;25(1):16-23. doi: 10.1016/j.jmu.2016.09.003. Epub 2016 Nov 15.

Authors

Li-Tan Yang^{1

2}, Wei-Chuan Tsai², Chwan-Yau Luo³, Yi-Heng Li², Liang-Miin Tsai²

Affiliations

¹ Department of Internal Medicine, Tainan Hospital, Ministry of Health and Welfare, Tainan, Taiwan.
² Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
³ Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.

Abstract

Background: Impaired left atrial (LA) reservoir deformation has been found to be associated with poor functional capacity and outcomes in severe chronic mitral regurgitation (MR). Among patients with primary MR (valve incompetence due to mitral valve pathology), we focus on Carpentier II classification (prolapse or flail mitral valve) and aim to investigate determinants for decreased LA reservoir deformation and its impact on LA remodeling in severe MR.

Methods: Among 159 consecutive patients with severe chronic Carpentier II MR (left ventricular ejection fraction ≥ 60%), 55 underwent follow-up echocardiography, which was compared with their baseline study. We used the change of LA volume index as the rapidity of LA remodeling, LA eccentricity index as LA sphericity, and peak LA reservoir strain as well as reservoir strain rate (LASR_R) derived from two-dimensional speckle-tracking echocardiography as LA reservoir function.

Results: Older age, elongated left atrium, increased LA volume index, as well as reduced left ventricular global longitudinal strain and LA ejection fraction all linked to a poor baseline LASR_R (all p < 0.001). A second echocardiography during a mean follow-up of 15.3 ± 8.3 months revealed an enlarged left atrium (increased interval change of LA volume index; p < 0.001). In multivariate analysis, only the difference between the baseline and follow-up LASR_R values (Δ: LASR_R; odds ratio (OR) 0.037, 95% confidence interval (CI) 0.003-0.496, p = 0.013) predicted accelerated LA remodeling. A poor baseline LASR_R was significantly associated with its profound deterioration during the follow-up period (β: = -0.424, p = 0.002).

Conclusion: In severe chronic Carpentier II MR, a reduced follow-up LASR_R predicted future accelerated LA remodeling. Patients with a poor baseline LASR_R are at a higher risk of its deterioration.

Keywords: left atrium; mitral regurgitation; speckle-tracking echocardiography; strain rate.