Jadranka Stojanovska MD, MS, Presenter: Nothing to Disclose

Ella A. Kazerooni MD, Abstract Co-Author: Nothing to Disclose

Barry Howard Gross MD, Abstract Co-Author: Nothing to Disclose

Hakan Oral MD, Abstract Co-Author: Nothing to Disclose

To determine whether intrathoracic fat volumes are independently associated with the presence of atrial fibrillation (AF), severity of AF and outcome of radiofrequency ablation (RFA) using logistic regression analysis.

Institutional Review Board approval was obtained and patient consent was waived for this HIPPA-compliant retrospective study. A total of 231 patients, 169 with AF (75 with non-paroxysmal and 94 with paroxysmal) and 62 control patients, formed the study population. AF patients underwent computed tomography (CT) of the pulmonary veins and left atrium, and control patients underwent coronary CT. Intrathoracic fat volumes (extrapericardial and epicardial) were measured for both groups. Associations between presence & severity of AF and intrathoracic fat volumes were assessed using logistic regression analysis.

The epicardial fat volume remained statistically associated with the prevalence of AF [1.01 (1.003-1.03), p= 0.01], AF severity [1.008 (1.001-1.02), p=0.03], and recurrence of AF after RFA [1.009 (1.001-1.01), p=0.02] after adjustment for age, gender, and body mass index. Time to recurrence after ablation was shorter in patients who had larger epicardial fat volume than patients who did not (14± 15 days versus 22± 16 days, p=0.017). The epicardial fat volume was larger in the 78/169 AF patients (46%) who had AF recurrence after RFA compared to the 91/169 or (54%) who did not have recurrence (81 ± 47 mL versus 105 ± 56 mL, p=0.002).

Increased epicardial fat volume is associated with the presence of AF, AF severity, and higher probability of recurrence of AF after radiofrequency ablation.

Extensive epicardial fat is associated with earlier recurrences of AF after radiofrequency ablation that potentially may reduce the transmurality of radiofrequency ablation by affecting current and impedance dynamics. Quantification of epicardial fat on pre-procedural CT scan may identify patients with AF who will benefit from catheter ablation as a definitive treatment for AF.

Stojanovska, J, Kazerooni, E, Gross, B, Oral, H, Increased Epicardial Fat Volume Is Independently Associated with Atrial Fibrillation, Atrial Fibrillation Severity and Radiofrequency Ablation Outcome.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14004762.html