Sustained monomorphic ventricular tachycardia ablation from the aortic sinus of Valsalva

Introduction: The aim of this study was to delineate the electrophysiologic mechanisms of a novel type of ventricular tachyeardia (VT) originating from the aortic sinus of Valsalva. Methods and Results: Endocardial mapping was performed in four patients with symptomatic VT originating from the aortic sinus of Valsalva. Two patients suffered from dilative cardioniyopathy; the other two patients had no structural heart disease. Five VTs could be induced and terminated by programmed ventricular stimulation. Successful ablation was performed in the noncoronary sinus of Valsalva in three VTs and in the left aortic sinus in two. Abnormal (diastolic or presystolic) potentials were recorded during sinus rhythm (mean interval from the end of QRS complex to the potential 121 98 msec) and during VT (mean interval from the potential to QRS complex 64 +/- 45 msec) at effective sites in the aortic sinuses of Valsalva. Concealed entrainment was demonstrated at all successful sites. VT recurred in one patient after 1 month, whereas no recurrences were observed during follow-up of 8 +/- 6 months in the other three patients. Conclusion: Reentry constitutes one mechanism of VT originating from the aortic sinus of Valsalva. Entrainment mapping is useful to characterize the reentrant circuit of these VTs and to guide ablation.