Abstract
BACKGROUND: Ischaemic chest pain can be originated by different causes. Among all, coronary fistulas are rarely the reason. Such entities are usually asymptomatic and can be diagnosed by echocardiography or coronary angiography. In an even rarer scenario, coronary fistulas might dilate and form an aneurysm. CASE SUMMARY: We report the case of a 62-year-old patient who was initially referred to the emergency department for stable angina. Coronary angiography and computed tomography scan showed a giant aneurysm relating to a coronary fistula with a course from the circumflex coronary artery to the superior vena cava. The aneurysm was critically compressing the left anterior descending coronary artery. It was confirmed and resolved by surgery. DISCUSSION: Giant aneurysms of a coronary fistula are very uncommon entities. We describe a rare case of angina caused by extrinsic compression of the left anterior descending artery from a giant aneurysm of a coronary fistula.