Intracoronary and Tailored Vasodilator Therapy for Refractory Ventricular Fibrillation Storm Triggered by Multivessel Coronary Spasm: A Case Report

Background Multivessel vasospastic angina (VSA) is a recognised cause of malignant ventricular arrhythmia. Although guideline-directed vasodilator therapy and implantable cardioverter-defibrillators (ICDs) are recommended, some patients remain at risk for refractory ventricular fibrillation (VF). To date, no strategy has been established for these cases. Case summary A 67-year-old man experienced a VSA-related ST-elevation myocardial infarction complicated by VF, leading to subcutaneous ICD implantation. The patient remained stable for one year on medications without non-adherence or device therapies. One year later, the patient experienced out-of-hospital cardiac arrest due to a recurrent VF storm. Coronary angiography revealed intact arteries with diffuse spasms. Despite mechanical circulatory support, VF persisted and was unresponsive to repeated ICD shocks and external defibrillation. Repeat coronary angiography confirmed multivessel spasm. Intracoronary vasodilator administration, followed by defibrillation-terminated VF and subsequent tailored optimisation of oral vasodilator therapy, prevented recurrence. Discussion This case demonstrates that intracoronary vasodilator therapy combined with personalised drug adjustment may represent a valuable therapeutic option for refractory VF storms in multivessel VSA beyond conventional management.