Three‐dimensional mapping discovered arrhythmic substrate missed in the initial diagnosis of idiopathic ventricular fibrillation

Figures

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  FIGURE 1. A, Electrocardiogram on the patient's first admission when he was 33 y old. Fast ventricular tachycardia including a partially polymorphic waveform and a heart rate of 330 beats per min were recorded. B, Electrocardiogram at rest. Right bundle branch block was observed

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  FIGURE 2. A, Intracardiac implantable cardioverter defibrillator record of a monomorphic ventricular tachycardia (VT). A monomorphic VT (mean cycle length, 185 ms) was recorded and consistently triggered by the same premature ventricular contraction (PVC). B, Electrocardiogram at rest before the first ablation therapy. Complete right bundle branch block and a single PVC of a left bundle branch block configuration with an inferior axis observed

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  FIGURE 3. A, Electrocardiogram on admission during a ventricular tachycardia (VT) storm before the third ablation therapy. The morphology of the VT was a left bundle branch block configuration with an inferior axis. Its estimated origin was the right ventricular outflow tract. B, Three‐dimensional (3D) voltage map during sinus rhythm. Anterior to posterior view of the 3D mapping of the right ventricle in the third ablation session is superimposed on a preoperative figure of Computed Tomography. Blue tag indicates a successful ablation site for premature ventricular contraction and ventricular tachycardia. White tag indicates a good pacemap with a score of 96. AP view, anterior‐posterior view; PV, pulmonary valve; TV, tricuspid valve; RV apex, right ventricular apex. C, Intracardiac electrogram of the success site during the third ablation therapy. The distal part of the ablation catheter (ablation [ABL] 1 U and 1‐2) detected depolarization 34 ms earlier than any other leads of the electrocardiogram. HBE, His bundle electrogram; RVA, right ventricular apex