A case report of a giant coronary artery aneurysm masquerading as a ventricular mass.

Background: A coronary artery aneurysm is a dilation exceeding 1.5 times the diameter of the patient's largest coronary vessel. They are rare, varying in prevalence between 1.4 and 4.9%. Additionally, they carry a high risk of potential complications, including thrombosis and myocardial infarction, with a risk of rupture. We present an interesting case of a patient with initial imaging suggesting a mass in the right ventricle. Case summary: This patient initially presented with acute hypoxic respiratory failure related to pulmonary oedema. His course was complicated by symptomatic ventricular tachycardia and an inferoposterior myocardial infarction. Further investigation revealed a left anterior descending artery and circumflex artery thrombosed aneurysm projecting into the right ventricle. Multimodal imaging was used to arrive at his diagnosis. He continues to do well on medical therapy for coronary artery disease and heart failure. Discussion: Clinicians should be vigilant for this rare pathology, which may be easily missed yet poses a high mortality risk. Our case demonstrates the benefit of multimodal imaging, as this patient's aneurysm was initially mistaken for a ventricular mass.