Electrophysiological characteristics and radiofrequency catheter ablation of atrial arrhythmias originating from superior vena cava

AIM To investigate the strategy of radiofrequency catheter ablation (RFCA) of atrial arrhythmias originating from superior vena cava (SVC). METHODS The study enrolled 14 patients undergoing electrophysiological examination and radiofrequency catheter ablation of atrial arrhythmias originating from SVC. The origin site with the earliest atrial activation was mapped under the guidance of traditional mapping technique or cardiac three-dimensional (3D) mapping system combined with SVC angiography. RFCA of the SVC origin was performed by focal, segmental or circular ablation. The electrophysiologic features and the strategies of RFCA in the 14 patients were analyzed. RESULTS RFCA eliminated atrial tachycardia (AT) in five patients by focal ablation and eliminated premature atrial contraction (PAC), which might trigger atrial fibrillation (AF) by segmental and circular isolation of SVC, respectively, in six and three patients. After isolation of SVC, three patients had automatic electrical activity in SVC. CONCLUSION Atrial arrhythmias originating from SVC has some typical cardiac electrophysiological characteristics. RFCA could eliminate focal AT or PAC originating from SVC by focal ablation and segmental or circular isolation of SVC.