Abstract
BACKGROUND: Coronary vasospasm (CV) is a rare cause of malignant ventricular arrhythmia and cardiac arrest. It typically presents with chest pain and marked ST-segment elevation. CASE SUMMARY: We present the case of a 61-year-old man with recurrent malignant ventricular arrhythmia and implantable defibrillator shocks without preceding chest pain. The diagnosis of CV remained elusive for 3 months despite extensive investigation. Close inspection of telemetry revealed progressive ST-segment depression and T-wave inversion before arrest. Coronary angiography with low-dose acetylcholine testing revealed multivessel vasospasm. Vasodilator therapy was initiated with rapid elimination of ventricular arrhythmia. DISCUSSION: This case highlights that cardiac arrest due to CV may present without the classical features of chest pain or ST-segment elevation, underscoring the value of provocation testing in unexplained arrhythmia. TAKE-HOME MESSAGES: CV may present without preceding angina or ST-segment elevation. Careful electrocardiogram review and early provocation testing can identify vasospasm and guide therapy.