Aneurysms of the Ascending Aorta

Abstract

Aneurysms of the ascending aorta present a special challenge to primary care physicians, internists, and cardiac surgeons because they remain asymptomatic until they present with either dissection or rupture. This review article is based on a selective search of the literature. In the elderly, aneurysms of the ascending aorta are mainly caused by atherosclerosis. In younger patients, the most common cause is Marfan syndrome; less commonly, younger patients may have Loeys-Dietz syndrome, non-syndromic familial aortic aneurysms, or aortic valve malformations. Genetic variants predisposing to the development of sporadic aortic aneurysms have recently been identified. The risk of rupture and dissection depends on the aortic diameter: when the diameter exceeds 55 mm, surgery improves the outcome, as the risk of surgical complications is lower than the mortality due to rupture or dissection. A more accurate prognosis can be obtained by normalizing the aortic diameter to the body surface area. For patients with Marfan syndrome or a bicuspid aortic valve, the indications for surgery should be determined on an individual basis, depending on additional risk factors. Randomized treatment trials are lacking. The medical management of aneurysms of the ascending aorta consists of monitoring the size of the aneurysm, controlling blood pressure, and treating any cardiovascular risk factors. Patients with Marfan syndrome benefit from preventive treatment with beta-blockers. Advances in the pathophysiological understanding of aortic aneurysms have led to the testing of new types of treatment, e.g., with AT1 antagonists. With the aid of a risk-based treatment strategy, surgery can be properly timed to prevent dissection, which is usually lethal when it occurs. More research is needed on the pathogenesis of this condition so that better preventive treatments can be developed.