Editorial to “Bipolar radiofrequency catheter ablation between the left ventricular endocardium and great cardiac vein for refractory ventricular premature complexes originating from the left ventricular summit”

Although rapid and dramatic development of mapping technology using 3-D mapping system in recent years, operators sometimes may face difficult cases for ablation. One specific reason is the localization of the origin of tachycardia. Because left ventricular (LV) wall has considerable thickness, it may be difficult to deliver appropriate amount of energy for successful ablation of tachycardia originating from “nonendocardial” area. The epicardial approach is one of the options for epicardial origin although it will need specific technique. However, intramural origin is probably mostly protected area from ablation energy. In Tokioka's report, they have experienced three cases with ventricular arrhythmia originated from LV summit and all cases were refractory for catheter ablation using standard endocardial approach. They carefully tried bipolar ablation in between LV endocardium and great cardiac vein using 8-mm tip irrigation catheter. As a result, they successfully and safely ablated all cases. Theoretically, local ablation energy depends on the convergence density of the electromagnetic radiation. In standard unipolar ablation, electromagnetic radiation will be dispersed depending on the distance from the catheter tip, and appropriate aggregation of energy cannot be expected in deeper lesion. In contrast, bipolar ablation does not cause dispersion of electromagnetic radiation and it can be expected to ablate deeper lesion in between two electrodes which deliver radiofrequency energy.1 In the three cases in the report, they probably obtained successful results through this specific mechanism of bipolar ablation. This method is expected to be highly useful in specific cases with intramural lesion. However, the safety is most important issue. Because the methodologies of reported bipolar ablation varied depending on the difference in the systems in reported years,2 standard method should be established for the expansion of this method through the reports in future. The author declare no conflict of interests for this article.