Giant Right Coronary Artery Aneurysm With Left Ventricular Fistula: A Rare Coronary Anomaly.

backgroundGiant coronary artery aneurysms are rare vascular anomalies (<0.02% prevalence). Fistulous drainage into the left ventricle (LV) is exceptionally uncommon and may present with malignant arrhythmias or sudden cardiac arrest. CASE SUMMARY: A 65-year-old man with hypertension and presumed cardiomyopathy experienced an out-of-hospital ventricular tachycardia arrest while on pilgrimage. Multimodality imaging revealed a 42-mm right coronary artery aneurysm with a fistulous connection to the LV, a true inferobasal LV aneurysm, and ascending aortic dilation. A multidisciplinary team recommended surgical repair and implantable cardioverter-defibrillator for secondary prevention, but the patient declined all invasive interventions after thorough counseling. He was managed medically and discharged in stable condition with a structured surveillance plan. DISCUSSION: This case highlights a rare triad of right coronary artery aneurysm, LV fistula, and true LV aneurysm, presenting as cardiac arrest. It underscores the importance of imaging, patient-centered decision-making, and follow-up in managing rare coronary anomalies. TAKE-HOME MESSAGES: Multimodality imaging is essential for diagnosing rare coronary anomalies. Patient autonomy can override guideline-driven recommendations.