Natural history, clinical consequences, and morphologic features of coronary arterial aneurysms in adults.

Clinical and morphologic features are described in 20 adults (15 men) aged 17 to 85 years (mean 56) who at necropsy were found to have ≥1 aneurysm in ≥1 of their 3 major (right, left anterior descending, and left circumflex) epicardial coronary arteries. Of the 34 coronary aneurysms in the 20 patients (single in 10 patients, ≥2 in 10 patients), 27 (79%) contained intra-aneurysmal thrombi, and in each, the thrombus severely narrowed the lumen. Additionally, atherosclerotic plaque was present in the aneurysmal wall in all 27 aneurysms containing thrombi and also in the major coronary arteries uninvolved by aneurysm. The causes of the aneurysms in the 16 patients with intra-aneurysmal thrombi were therefore considered atherosclerotic. In the other 4 patients, with 7 aneurysms, none contained intra-aneurysmal thrombus or atherosclerotic plaque, and the aneurysms were considered congenital. Clinical diagnosis of coronary aneurysm was not made in any of the 20 patients, but none had proper imaging studies during life. Despite the coronary aneurysms and the associated luminal narrowing, only 8 patients (40%) had left ventricular wall scarring or necrosis or clinical evidence of myocardial ischemia. Proper therapy remains ill defined.