Radiofrequency Catheter Ablation from the Epicardial Sites for Ventricular Arrhythmias Originating from the Left Ventricular Summit—Two Case-Reports—

Introduction: We report 2 cases of ventricular arrhythmias (VAs) originating from the left ventricular summit (LVS) which required radiofrequency energy (RF) application in the great cardiac vein (GCV) and/or the epicardium for treating VAs. Case 1: Sixty-five year-old female with idiopathic VAs underwent RF-catheter ablation (CA). The earliest activation site of VAs was observed in GCV, to which left descending coronary artery (LAD) run close. Sufficient RF delivery could not be performed due to the concerns about the injury to LAD, and the procedure resulted in a transient therapeutic effect. Case 2: Fifty-one year-old male suffering from VAs associated with non-ischemic cardiomyopathy underwent RF-CA. In 1st session, the earliest activation site of VAs was recognized in GCV, however, RF-CA application in GCV failed to abolish VAs. In 2nd session with the subxiphoidal pericardial approach, the earliest site was located at LVS extremely close to LAD. Despite the multiple RF applications in the vicinity sites of that portion, we were unable to abolish VAs. Conclusion: In sporadic cases, epicardial approach is required to eliminate VAs. However, the discretion and attention have to be paid in order to avoid the serious complications for treating VAs originating from LVS.