Improved Left Atrial Function in CRT Responders: A Systematic Review and Meta-Analysis

• Main Authors: Ibadete Bytyçi, Gani Bajraktari, Per Lindqvist, Michael Y. Henein
• Format: Article
• Language: English
• Published: MDPI AG 2020-01-01
• Series: Journal of Clinical Medicine
• Subjects: left atrial strain; cardiac resynchronization therapy; heart failure
• Online Access: https://www.mdpi.com/2077-0383/9/2/298

Cardiac resynchronization therapy (CRT) is associated with reverse left atrial (LA) remodeling. The aim of this meta-analysis was to assess the relationship between clinical response to CRT and LA function changes. We conducted a systematic search of all electronic databases up to September 2019 which identified 488 patients from seven studies. At (mean) 6 months follow-up, LA systolic strain and emptying fraction (EF) were increased in CRT responders, with a &#8722;5.70% weighted mean difference (WMD) [95% confidence interval (CI) &#8722;8.37 to &#8722;3.04, <i>p</i> &lt; 0.001 and a WMD of &#8722;8.98% [CI &#8722;15.1 to &#8722;2.84, <i>p</i> = 0.004], compared to non-responders. The increase in LA strain was associated with a fall in left ventricle (LV) end-systolic volume (LVESV) <i>r</i> = &#8722;0.56 (CI &#8722;0.68 to &#8722;0.40, <i>p</i> &lt; 0.001) and an increase in the LV ejection fraction (LVEF) <i>r</i> = 0.58 (CI 0.42 to 0.69, <i>p</i> &lt; 0.001). The increase in LA EF correlated with the fall in LVESV <i>r</i> = &#8722;0.51 (CI &#8722;0.63 to &#8722;0.36, <i>p</i> &lt; 0.001) and the increase in the LVEF <i>r</i> = 0.48 (CI 0.33 to 0.61, <i>p</i> = 0.002). The increase in LA strain correlated with the increase in the LA EF, <i>r</i> = 0.57 (CI 0.43 to 0.70, <i>p</i> &lt; 0.001). Thus, the improvement of LA function in CRT responders reflects LA reverse remodeling and is related to its ventricular counterpart.