Adipose tissue of atrial septum as a marker of coronary artery disease

Background: Paracrine effects of epicardial adipose tissue may promote coronary atherosclerosis. Adipose tissue is the main determinant of atrial septum thickness. The association between atrial septum thickness and coronary artery disease (CAD) has never been studied. Methods: We studied 75 patients who underwent coronary angiography and echocardiography within 1 week (mean [± SD]duration, 2.0 ± 2.0 days). Atrial septum thickness, representing adipose tissue, was identified and measured with two-dimensional transthoracic echocardiography. Angiographic data were analyzed for the presence, extent, and severity of CAD, using a standardized 27-segment classification. Any CAD was defined as the presence of stenosis of any severity in at least one coronary vessel. The number of segments with a coronary artery with at least 20% stenosis (coronary artery greater even than 20 [CAGE ≥ 20] score) was recorded. Results: The mean atrial septum thickness was 1.5 ± 0.4 cm (median, 1.42 cm; range, 0.74 to 2.55 cm). In a simple linear regression analysis, we found no significant correlation between atrial septum thickness and clinical variables (p > 0.05). However, we found a significant correlation between atrial septum thickness and any CAD (p = 0.03), which persisted after controlling for age, gender, and body mass index (p = 0.03). Patients in the lowest quartile of atrial septum thickness had a lower proportion of subjects with any CAD (p = 0.02) and a lower median CAGE ≥ 20 score compared to other quartiles (p = 0.04). Conclusion: Adipose tissue of the atrial septum, represented by atrial septum thickness, is associated with the presence of CAD.