[Ventricular fibrillation secondary to radiofrequency application in ventricular tachycardia ablation]

Radiofrequency catheter ablation has become a first line therapy for several types of tachycardias because of its high efficacy and low complication rate. The development of proarrhythmic complications due to a direct effect of radiofrequency is very unusual. We describe a patient with previous myocardial infarction and well tolerated sustained monomorphic ventricular tachycardia who underwent catheter ablation of the tachycardia substrate. During two of the radiofrequency applications, ventricular fibrillation developed and external defibrillation was required.