Aim. To identify the relationship of atrial fibrillation (AF) with features of lesions of the main coronary arteries or primary branches in patients with coronary artery disease (CAD).Material and methods. From the local database of coronary angiography, 6978 patients with hemodynamically significant (50% of the lumen and more) coronary lesions were selected. The main group consisted of 205 patients with AF. To create an age-matched comparison group, 810 patients without AF were selected from the remaining 6773 patients using a method based on equalizing the frequency distributions.Results. Patients with AF accounted for 2,9% of all patients with hemodynamically significant coronary stenosis. In patients with AF, obesity (56,6% vs 44,5%, p=0,002) and severe (III-IV) classes of chronic heart failure (CHF) according to NYHA classification (51,8% vs 22,8%, p<0,001) was more often detected. These patients had a higher mass index of the left ventricular (LV) (170,9±41,2 g/m2 vs 150,0±34,7 g/m2, p<0,001), higher size index of the right ventricle (RV) (13,8±2,1 mm/m2 vs 13,1±1,3 mm/m2, p<0,001); hemodynamically significant mitral (MR) (49,7% vs 15,9%, p<0,001) and aortic regurgitation (AR) (6,7% vs 1,5%, p<0,001) was also more often detected. Patients with AF more often had lesions of the right coronary artery (RCA) (90,2% vs 82,1%, p=0,005) and calcification of the coronary arteries (24,3% vs 14,8%, p=0,001), less often — the left type of coronary circulation (6,6% against 12,0%, p=0,029). According to the results of multivariate analysis, the presence of significant MR increased the risk of AF by 3,5 times, AR increased by 3,1 times. With CHF worsening to III-IV NYHA classes, the risk of AF increased by 2,1 times, with the presence of RCA — by 80%, obesity of 2 or 3 degrees — by 40%. An increase in the RV size indices for each mm/m2 increased the risk of AF by 14%; in the LV myocardium mass for each g/m2 — by 0,5%.Conclusion. Angiographic predictor of AF in patients with CAD is the RCA lesion
