Mechanical and substrate abnormalities of the left atrium assessed by 2-dimensional speckle-tracking echocardiography (2D-STE) versus by electroanatomic mapping (EAM) system in patients with atrial fibrillation

Background: Strain imaging has been used as a surrogate for left atrial (LA) structural remodelling. Low-voltage zones (LVZs) obtained by 3D-EAM were correlated with local conduction delays and atrial fibrillation (AF) patients with >5% LVZs had higher recurrence rate post ablation. We aimed to clarify the relationship between early phase LA remodelling using 2D-STE and voltage mapping in patients with AF.

Methods: A prospective study of consecutive patients undergoing AF ablation. The percentage of standard deviation of the time to peak strain (%SD-TPS) in LA was analysed by 2D-STE (TOM Tec, Inc. Munich). High-density contact LA bipolar voltage maps were constructed before ablation using CARTO 3D-EAM (PentaRay® multi-electrode mapping catheter and CONFIDENSE™ module, Biosense Webster). LVZs were determined with local bipolar amplitudes of <0.1mV,

Results: Twenty-six patients were enrolled. Compared with non-LVZs group (n=14), LVZs group (n=12) included significantly older patients with higher CHAD₂VASC₂ score, lower ejection fraction, higher E/e’ and E/A ratio and larger LAs (pLVZs group had significantly lower %SD-TPS values (9.7±5 % vs. 20.3±6 %) (p<0.05). LVZs% measured by different amplitudes (%SD-TPS (r= -0.703, r= -0.752 and r= -0.831, respectively) (Spearman correlation, pUsing logistic regression, LVZs≥5% in amplitudes ,

Conclusions: LVZs≥5% has negative association with atrial %SD-TPS. Patients with larger atrial scar tissue demonstrated %SD-TPS <15.67% (in