Myocardial infarction in a patient with Down's Syndrome: A case report and review of the literature

Down's Syndrome (DS) was reported to be an atherosclerosis-free model in 1977, an assertion that has been debated for the past 20 years. Myocardial infarction in a patient with DS and a structurally normal heart has not been reported previously in patients with DS. Although hyperhomocysteinemia has been associated with premature coronary disease, DS patients have low homocysteine levels which purportedly explain the rarity of atherosclerosis in DS. Autoimmune disorders, common in DS, have been associated with coronary arteritis and myocardial infarction; however, patients with DS rarely manifest coronary disease. The discovery of the cystathionine β-synthase (CBS) gene on chromosome 21 and lower homocysteine levels in DS patients have renewed interest in a mechanism that diminishes atheroma in DS patients. We present a case of myocardial infarction from coronary artery disease in a patient with DS, autoimmune disorders, and a normal homocysteine level who was treated successfully with percutaneous transluminal coronary angioplasty. The patient's illness reflected an interplay of the above factors, and the case provides an opportunity to review the relevant literature on the relationship between DS and atherosclerosis.