Objective To investigate the impact of left atrial epicardial adiposity on recurrence of atrial fibrillation (AF) after catheter ablation.
Methods From 2009 to 2010, consecutive patients with AF who underwent circumferential pulmonary vein ablation guided by 3-D mapping system were enrolled in the retrospective study. Left atrial (LA) epicardial fat pad thickness was measured in consecutive cardiac CT angiograms performed for AF. Patients were grouped by AF burden: paroxysmal (n = 100), or persistent (n = 49) AF. The short-axis view was reconstructed as a plane perpendicular to the long axis of these 2 views at the level of the mid LA. In this short-axis view, the periatrial epicardial fat thickness was measured (in cm) as the shortest distance between the mid left atrium (LA) wall and 3 anatomic landmarks: oesophagus (LA-ESO), main pulmonary artery (LA-PA), and descending thoracic aorta (LA-TA) In a short-axis view at the mid LA, periatrial epicardial fat thickness was measured at the oesophagus (LA-ESO), main pulmonary artery, and thoracic aorta. The recurrence was defined as atrial tachyarrhythmia lasting more than 30 seconds beyond one month washout period.
Results In this study population, 100 had paroxysmal AF, and 49 had persistent AF, 49 patients were female. The association between AF burden by grade (paroxysmal 1, persistent 2). Differences in gender, age, LVEF, and comorbid factors were not statistically significant. Periatrial LA-ESO fat thickness was assessed by ordinal logistic regression. Univariately, LA-ESO, LA-TA, LA-PA, and LAD were significant predictor of AF burden. After adjusting for age, BMI, LA-TA, LA-PA and LAD, the association remained significant (odds ratio, 0.407; 95% CI, 0.246 to 0.673; P = 0.00046).
There was no loss to follow-up after 12 months. Of 149 patients, 98(65.8%) remained free of recurrence after a single ablation procedure. The recurrence patients had a significantly thicker LA-ESO fat pad than the normal patients after ablation. By logistic regression modelling, after adjusting for AF burden, LAD, age, and comorbid factors, LA-ESO fat depots were individually predictive of the recurrence of AF (P = 0.002, OR = 0.444.95%CI: 0.268–0.734).
Conclusions Left atrial epicardial adiposity is associated with the burden of AF, and poorer outcomes after AF ablation. LA-ESO fat depots were individually predictive of the recurrence of AF.