Novel V‐V‐A response after right ventricular entrainment pacing for narrow QRS tachycardia: What is the mechanism?

A 76-year-old woman without overt structural heart disease was referred to our institution for catheter ablation of narrow QRS complex tachycardia (157 beats/min). The tachycardia was sustained despite occasional absence of retrograde P waves (Figure 1A). A 12-lead surface electrocardiogram recorded during sinus rhythm showed no preexcitation. This article is protected by copyright. All rights reserved.