Giant coronary aneurysm with ventricular fistula is rare. Due to the limited data from randomised clinical trials, therapeutic strategies for coronary aneurysms predominantly rely on on case series and anecdotal evidences. Reporting cases that provide practical experience in managing these aneurysms is therefore crucial. In this article, we report a rare case of a successful surgical management for a thrombosed giant left coronary aneurysm with right ventricular fistula, which is larger than any previously reported cases.

Kawasaki disease is usually self-limited, but it can lead to aneurysm, stenosis, thrombosis, and myocardial infarction in the coronary arteries. The most important complication of Kawasaki disease is coronary artery aneurysm. Coronary artery aneurysm or ectasia may be seen in 15–25% of patients who do not receive treatment. It develops in 5% of children who receive intravenous immunoglobulin at the appropriate time. Acute myocardial infarction is the most important cause of morbidity and mortality in Kawasaki patients with giant aneurysms. We present a 10-year-old girl who had a history of giant aneurysm in the coronary arteries and underwent percutaneous coronary intervention due to anterior myocardial infarction.

Giant coronary aneurysms secondary to Kawasaki disease are rare, but a very severe complication. Delayed diagnosis and appropriate treatment of the disease is a well-known risk factor for coronary aneurysms.