Automated Echocardiographic Assessment of Left Atrial Remodeling in Atrial Fibrillation Using Dynamic HeartModel and AutoStrain LA

PURPOSE: To compare left atrial (LA) size, emptying function, and strain among non-atrial fibrillation (AF) controls, patients with paroxysmal AF (PAF), and patients with persistent AF (PeAF) using automated 3D Dynamic HeartModel (DHM) and AutoStrain LA, and to examine their association with AF stage. METHODS: This retrospective study included 210 participants: 70 non-AF controls, 70 patients with PAF, and 70 patients with PeAF. Controls and patients with PAF were examined during sinus rhythm; acquisition rhythm in PeAF was not uniformly documented. LA volumes and LA ejection fraction (LAEF) were measured using automated 3D DHM, and LA strain was assessed using AutoStrain LA. AF stage was coded as 0, 1, and 2. Multivariable regression analyses evaluated associations with LA volume index (LAVI), LAEF, and LA reservoir strain (LASr). Reproducibility was assessed using intraclass correlation coefficients. RESULTS: across controls, PAF, and PeAF, whereas LAEF decreased from 65.37% ± 7.39% to 50.70% ± 8.28% and 23.34% ± 6.58%, and LASr decreased from 38.00% to 25.05% and 10.20%, respectively (all p < 0.001). After adjustment, AF stage remained associated with higher LAVI (B = 16.43; 95% CI, 13.69-19.17), lower LAEF (B = -19.11; 95% CI, -20.58 to -17.64), and lower LASr (B = -12.37; 95% CI, -13.57 to -11.18; all p < 0.001). Findings were similar after excluding participants with heart rate >100 bpm. Intra-/inter-observer ICCs were 0.989/0.986 for LAVI, 0.975/0.964 for LAEF, and 0.983/0.977 for LASr. CONCLUSION: Automated 3D DHM and AutoStrain LA demonstrated graded LA enlargement, reduced emptying function, and impaired reservoir strain across AF temporal patterns. These automated measurements showed favorable reproducibility and may help characterize LA structural and functional remodeling in patients with AF.