A case of a late fatal complication after atrial fibrillation ablation related to a prolonged QT interval unmasked by atrial fibrillation ablation.

A 79-year-old woman with a history of atrial fibrillation (AF) ablation was referred to our hospital for ventricular fibrillation, which was terminated by an automated external defibrillator. The heart rate corrected QT interval was 489 ms. The electrocardiogram monitoring recorded a polymorphic ventricular tachycardia (VT) reproducibly induced by a single morphology premature ventricular contraction (PVC). Therefore, we performed a trigger PVC ablation and implanted an implantable cardioverter defibrillator. No VT events were observed for at least one year after the ablation. A prolonged QT interval after the AF ablation should be carefully noted because it could introduce fatal complications. <Learning objective: A rare late fatal complication of ventricular tachycardia (VT) after atrial fibrillation (AF) ablation can occur even more than one month after the AF ablation. The AF ablation might have an adverse effect on the masked prolonged QT interval. A trigger ablation of the polymorphic VT was helpful to control lethal VTs.>.