A 48-year-old man suffered from acute coronary syndrome in 1978. Coronary angiography was performed at that time and showed 99% stenosis of the right coronary artery, 100% of the left circumflex branch, and 50% of the left ascending artery. He received conservative therapy. Five years later (ie, 1983), coronary angiography showed complete occlusions of the 3 major coronary arteries. Rich collateral circulation had developed distal to all 3 major coronary trees. The patient and his family rejected invasive therapies such as coronary-artery bypass graft or percutaneous coronary intervention. Cardiac catheterizations were performed in 1996, 2001, and 2007, but angiographic follow-up studies showed no change in either the coronary atherosclerosis or the collateral circulation. The left ventricular ejection fraction has been maintained at >60%. During the 20-year follow-up, he has had refractory angina, but has not suffered from acute coronary syndrome, congestive heart failure, or critical arrhythmia.