The coronary sinus: passive bystander or source of arrhythmia?

The coronary sinus provides access to the epicardial space of the heart allowing ablation of epicardial accessory pathways, foci of ventricular arrhythmia, and arrhythmogenic areas such as the vein or ligament of Marshall. In addition, its musculature may form atrioventricular accessory connections, participate in macroreentrant atrial arrhythmias, and generate foci of microreentrant atrial tachycardia and fibrillation. Thus, the coronary sinus may serve both as a bystander to arrhythmia circuits as well as an original source of cardiac arrhythmia.