Idiopathic ventricular fi...

A 30-year-old Japanese man with no family history of heart disease or sudden cardiac death was diagnosed with idiopathic ventricular fibrillation (VF) 10 years ago and underwent ICD implantation. RFCA of the triggered PVC was attempted but unsuccessful due to no inducibility. The patient experienced polymorphic nonsustained ventricular tachycardia reproducibly from a short coupling period of the identical morphology of PVC during physical activity, as shown in Figure 01, and various antiarrhythmic drugs were used without success. Blood tests and echocardiography showed no abnormalities, and signal-averaged electrocardiography showed no late potential. During the second RFCA, mapping was performed, and delayed potentials were observed in the inferior wall region at the base of the ventricle. However, j-wave and epicardial potentials were not considered transparent arrhythmogenic substrates. Ablation of the endocardium at the site of earliest excitation rendered PVC non-inducible, and VF was not inducible with any programmed stimulation. After 18 months of follow-up, there was no recurrence of VF.