Objectives: The present study reports on the complementary role of two nonpharmacological options of antiarrhythmic therapy.
Background: Catheter ablation, antitachycardia surgery, and the implantable cardioverter defibrillator (ICD) have become important tools in the management of ventricular tachyarrhythmias. However, the emergence of ventricular tachyarrhythmias after implantation of an ICD is possible because the arrhythmogenic substrate is not affected.
Patients and methods: Six of 180 patients developed frequent episodes of monomorphic ventricular tachycardia (n = 2) or incessant ventricular tachycardia (n = 4) following implantation of an ICD and underwent radiofrequency (RF) catheter ablation. Catheter ablation was performed using a RF generator HAT 200. Energy was delivered between a 4-mm tip electrode of the ablation catheter and a patch electrode.
Results: Catheter ablation was done 6.8 +/- 5 months following ICD implantation; 6 +/- 2.2 RF impulses were delivered at the site of origin of ventricular tachycardia characterized by early endocardial activation during ventricular tachycardia, identical pace mapping and long latency between stimulus, and QRS-complex in five patients. New bundle branch reentry was the underlying mechanism of ventricular tachycardia in one patient. RF catheter ablation resulted in termination of incessant ventricular tachycardia. Immediately postablation, the documented ventricular tachycardia was rendered noninducible in all patients. No ICD malfunctions have been observed. One patient died due to heart failure 24 hours after successful ablation of the incessant ventricular tachycardia. During a follow-up of 5-19 months, episodes of ventricular tachycardia recurred in four patients. All episodes could be controlled by the ICD without frequent cardioversions.
Conclusion: RF catheter ablation is a complementary therapeutic option in case of frequent or incessant ventricular tachycardia after ICD implantation.