Annular subaortic aneurysm resulting in sudden death

Abstract

Summary:A subvalvular aneurysm in a 34-year-old black woman developed beneath the left coronary cusp of the aortic valve and extended in the epicardium between the aortic root and left atrium. She was asymptomatic until she expired suddenly from myocardial ischemia caused by compression of the circumflex coronary artery by the aneurysm. A review of the literature reveals 13 reports of subaortic and 58 submitral aneurysms but only two instances of myocardial infarction secondary to coronary artery compression by spontaneous subvalvular aneurysms in either the subaortic or submitral position.

Development of a Subaortic Aneurysm Secondary to Disseminated Tuberculosis in a Child

“…Large aneurysms have been reported to compress the coronary arteries, causing myocardial infarction and sudden death [ [1] and [2]], or to compress the conduction system, causing heart blocks [9]. The ventriculogram in our patient demonstrated compression of the left coronary artery, although the electrocardiogram did not reveal any ischemic changes.…”

“…Chesler and colleagues [2] postulate that a dehiscence of the fibro-muscular union will result in aneurysm formation. The majority of these patients are of African ancestry, although similar conditions have been found to a lesser degree in other race groups [ [1], [3] and [4]]. They have also been described as a complication in patients with infective endocarditis, tuberculosis, and syphilis [ [4], [5], [6] and [7]].…”

“…The submitral aneurysms are more common than the subaortic type [1]. Subaortic and submitral aneurysms arise in the fibro-muscular rings of the aortic valve and mitral valve annuli, respectively [2].…”

Idiopathic subvalvular aortic aneurysm masquerading as acute coronary syndrome

“…However, with improvement in imaging techniques and wider availability, these aneurysms are recognised and reported more frequently than before. Previous case reports have described coronary arterial obstruction from external compression by large submitral LV aneurysms, but not so often with subaortic LV aneurysms 3 12. This is because subaortic aneurysms mostly occur in relation to the left coronary cusp of the aortic valve, are more restricted anatomically and do not reach large sizes as in the case of submitral aneurysms 1.…”

“…However, most cases arise as a sequelae of myocardial infarction,8 myocarditis due to tuberculosis, rheumatic fever, Chagas’ disease, syphilis and bacterial endocarditis 9–11. In the initial stages, they are mostly asymptomatic, and patients typically present in the second or third decade of life with heart failure from weakening of the annular ring and valvular incompetence 3. Life-threatening complications result from sudden rupture or extrinsic compression of nearby structures causing myocardial infarction (MI), malignant arrhythmias and thromboembolism 7…”