Assessing left atrial function in patients with atrial fibrillation and valvular heart disease using cardiovascular magnetic resonance imaging

Background Atrial fibrillation (AF) is common arrhythmia in valvular heart disease (VHD) and is associated with adverse outcomes. Hypothesis To evaluate the left atrial (LA) function in patients with AF-VHD by cardiovascular magnetic resonance imaging feature tracking (CMR-FT) using LA strain (epsilon(s)/epsilon(e)/epsilon(a)) and their corresponding strain rate (SRs/SRe/SRa). Methods This was a retrospective cross-sectional inter-reader and intra-reader reproducibility conducted from July 1, 2020, to January 31, 2021. A total of 39 patients with AF-VHD (rheumatic heart valvular disease [RHVD] [n = 22], degenerative heart valvular disease [DHVD] [n = 17]) underwent MRI scans performed with drug-controlled heart rate before correcting the rhythm and valves through maze procedure. Fifteen participants with normal cardiac MRI were included as healthy control. epsilon(s)/SRs, epsilon(e)/SRe, and epsilon(a)/SRa, corresponding to LA reservoir, conduit, and booster-pump function, were assessed using Feature Tracking software (CVI42 v5.12.1). Results Compared with healthy controls, LA global strain parameters (epsilon(s)/epsilon(e)/epsilon(a)/SRs/SRe/SRa) were significantly decreased (all p < 0.001), while LA size and volume were increased in AF-VHD group (all p < 0.001). In the subgroup, RHVD group showed lower LA total ejection fraction (LATEF) and strain data than DHVD group (12.6% +/- 3.3% vs. 19.4 +/- 8.6, p = 0.001). Decreased LATEF was significantly related to altered LA strain and strain rate, especially in epsilon(s), epsilon(e), and SRs (Pearson/Spearman r/rho = 0.856/0.837/0.562, respectively; all p < 0.001). Interstudy and intrastudy reproducibility were consistent for LA volumetry and strain parameters (intraclass correlation coefficient: 0.88-0.99). Conclusions CMR-FT can be used to assess the LA strain parameters, and identify LA dysfunction and deformation noninvasively, which could be a helpful functional imaging biomarker in the clinical treatment of AF-VHD.