Anatomical relationship of coronary sinus/great cardiac vein and left circumflex coronary artery along mitral annulus in atrial fibrillation before radiofrequency catheter ablation using 320-slice CT

Purpose: We evaluated anatomical relationships between the coronary sinus and great cardiac vein (CS/GCV) and left circumflex coronary artery (LCX) along the mitral annulus (MA) in patients with atrial fibrillation (AF) using 320-slice CT. Methods: Fifty-three patients with AF (44 males; mean 63 +/- 11 years; 28 paroxysmal, 10 persistent, and 15 permanent AF) underwent 320-slice CT. Double-oblique CT images perpendicular to the MA short axis were created every 10 degrees for 36 circumferential sections. The angle of 0 degrees corresponded to the 12 o'clock position. Results: CS/GCV-MA distance was greatest in the posterolateral MA. CS/GCV diverged from the LCX more widely in the lateral through posterolateral MA than the anterior through anterolateral MA. CS/GCV crossed the LCX in 51 patients (96.2%) and left main coronary artery in 2 patients (3.8%). Median angle of the CS/GCV-LCX crossing point was at 40 degrees but ranged widely (0 degrees to 150 degrees) and was more frequent in the anterior and anterolateral MA than in the lateral, posterolateral, and posterior MA (31.4%, 45.1%, 11.8%, 11.8%, and 0%, respectively; P < 0.01). CS/GCV crossed over the LCX in 39 patients and under the LCX in 12 patients. Range of the CS/GCV-LCX overlapping course increased significantly as the CS/GCV-LCX crossing point neared the CS ostium. Correlation coefficient between the range of the overlapping course and crossing point angle was 0.78. Conclusions: Anatomical relationships between CS/GCV and LCX greatly varied in location and proximity among AF patients. Interventional electrophysiologists should know the potential risk for LCX injury when radiofrequency energy is delivered within the CS/GCV. (C) 2013 Elsevier Ireland Ltd. All rights reserved.