Left atrial epicardial adiposity and atrial fibrillation.
BACKGROUND
Atrial fibrillation (AF) has been linked to inflammatory factors and obesity. Epicardial fat is a source of several inflammatory mediators related to the development of coronary artery disease. We hypothesized that periatrial fat may have a similar role in the development of AF.


RESULTS
Left atrium (LA) epicardial fat pad thickness was measured in consecutive cardiac CT angiograms performed for coronary artery disease or AF. Patients were grouped by AF burden: no (n=73), paroxysmal (n=60), or persistent (n=36) AF. In a short-axis view at the mid LA, periatrial epicardial fat thickness was measured at the esophagus (LA-ESO), main pulmonary artery, and thoracic aorta; retrosternal fat was measured in axial view (right coronary ostium level). LA area was determined in the 4-chamber view. LA-ESO fat was thicker in patients with persistent AF versus paroxysmal AF (P=0.011) or no AF (P=0.003). LA area was larger in patients with persistent AF than paroxysmal AF (P=0.004) or without AF (P<0.001). LA-ESO was a significant predictor of AF burden even after adjusting for age, body mass index, and LA area (odds ratio, 5.30; 95% confidence interval, 1.39 to 20.24; P=0.015). A propensity score-adjusted multivariable logistic regression that included age, body mass index, LA area, and comorbidities was also performed and the relationship remained statistically significant (P=0.008).


CONCLUSIONS
Increased posterior LA fat thickness appears to be associated with AF burden independent of age, body mass index, or LA area. Further studies are necessary to examine cause and effect, and if inflammatory, paracrine mediators explain this association.
Batal
Omar
O
Departments of General Internal Medicine, Cardiovascular Medicine, and Diagnostic Radiology, the Cleveland Clinic, Cleveland, Ohio 44195, USA.
Schoenhagen
Paul
P
Shao
Mingyuan
M
Ayyad
Ala Eddin
AE
Van Wagoner
David R
DR
Halliburton
Sandra S
SS
Tchou
Patrick J
PJ
Chung
Mina K
MK
D050154:Adiposity; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology*; D016009:Chi-Square Distribution; D017023:Coronary Angiography / Q000379:methods; D005260:Female; D006325:Heart Atria / Q000503:physiopathology; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010496:Pericardium / Q000000981:diagnostic imaging / Q000503:physiopathology*; D057216:Propensity Score; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed; D055815:Young Adult