Successful ablation of Purkinje ectopy–triggered ventricular fibrillation storm in a patient with orthotopic heart transplantation and severe SARS-CoV-2 pneumonia: a case report

Background: Catheter ablation is one of the most effective treatment options for patients with drug-refractory, scar-related monomorphic ventricular tachycardia (VT). In selected cases, catheter ablation also plays an important role in treatment of polymorphic VT (PMVT) and/or ventricular fibrillation (VF). Rarely, premature ventricular contractions (PVCs) originating from the Purkinje network can induce PMVT/VF. Ablation and elimination of these PVCs can prevent VF recurrences. Case summary: A 41-year-old patient with a history of orthotopic heart transplantation (HTX) 8 years before admission and newly diagnosed SARS-CoV-2 pneumonia was referred to our centre after experiencing several episodes of drug-refractory VF. An electrophysiological study showed ectopy-triggered VF originating from the anterior and posterior fascicles of the left bundle branch (LBB). Ablation of these PVCs from the LBB led to complete elimination of VF. A subcutaneous implantable cardioverter defibrillator was implanted as secondary prophylaxis. During the observation period of 6 months, no VF recurrence was observed. Conclusion: Identifying and eliminating the trigger (PVCs) can be life-saving and prevent VF in the specific cohort of HTX patients. High-density mapping using multipolar catheters with microelectrodes contributes significantly to our understanding of tachycardia mechanisms.