Correlation of left atrial wall thickness and atrial remodeling in atrial fibrillation : Study based on low-dose-ibutilide-facilitated catheter ablation

Abstract

Atrial remodeling plays a significant role during the progression of atrial fibrillation (AF). Left atrial wall thickness (LAT) is a subjective and easily acquirable indicator referring to structural remodeling. Therefore, we aimed to investigate the association between LAT and atrial remodeling substrate, and to explore the predictive role of LAT about strong maintenance substrate and poor response to catheter ablation. LAT was measured by cardiac computed tomography in 2 selected locations (roof and floor) in 100 persistent AF patients. Then the low-dose-ibutilide-facilitated catheter ablation was performed and atrial maintenance substrate was categorized as weak, mild, and strong, based on the response to circumferential pulmonary vein isolation or complex fractionated atrial electrograms ablation. During follow-up, the success rate was evaluated. LAT showed a progressive thickening tendency from weak, mild, to strong maintenance substrate (roof: 2.2mm vs. 2.6mm vs. 3.9mm, P 3.10mm might be the predictor to strong atrial maintenance substrate and poor response to ablation. LAT was associated with the remodeling extent of atrial maintenance substrate and might predict the response to catheter ablation. These findings could help the clinicians to select the appropriate ablative strategy and predict the complexity and prognosis before catheter ablation. Abbreviations: AF = atrial fibrillation, AT = atrial tachycardia, CFAEs = complex fractionated atrial electrograms, CPVI = circumferential pulmonary vein isolation, FACM = fibrotic atrial cardiomyopathy, LAD = left atrial diameter, LALD = left atrial length diameter, LAT = left atrial wall thickness, LATD = left atrial transverse diameter, LVEF = left ventricular ejection fraction, SR = sinus rhythm.