Epicardial and Pericardial Fat and the Risk of Post - Transcatheter Aortic Valve Implantation Atrial Fibrillation

Background: Little is known about predictors of new onset atrial fibrillation (AF) in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI). Lastly, there is increasing evidence supporting the association between epicardial fat volume and the risk of AF in the general population.

Objectives: To characterize the relationship between epicardial and pericardial fat volume and AF in patients with severe AS undergoing TAVI.

Methods: The prevalence of post-TAVI AF in our study was 10% (26 out of 253 patients). Aged, sex, and body mass index matched 10 patients who did not develop post-TAVI AF served as a control group. Pericardial, epicardial, and left atrial (LA) epicardial fat volume as well as the volume and area of the LA were quantified using ECG-gated, contrast enhanced 256-slice CT.

Results: The total epicardial and pericardial fat volume was significantly higher in patients with post-TAVI AF compared to the control group (206±85ml³ vs.150±24ml³; retrospectively, P = 0.04). Post-TAVI AF tended to have higher epicardial (84±47ml³ vs. 60±10ml³; retrospectively, P = 0.1), pericardial (85±44ml³ vs. 63±20ml³; retrospectively, P = 0.1), and LA epicardial fat volume (36±20ml³ vs. 26±5 ml³; respectively P = 0.1). Left atrial volume and area were similar in both groups.

Conclusions: Patients with post-TAVI AF had more epicardial and pericardial fat compared to controls, despite similar body mass index. Epicardial fat volume was associated with the presence of post-TAVI AF regardless of left atrium area or volume.