We report the case of a 40-year-old HIV-positive man, undergoing three-drug antiretroviral therapy for 2 years that included a protease inhibitor (ritonavir). The patient was admitted to our Coronary Care Unit with an acute anterior myocardial infarction. He smoked 20 cigarettes/day and had a family history of hypertension. At the time of hospitalization, triglyceride levels were found to be high (290 mg/dl). Metabolic alterations associated with the prolonged use of protease inhibitors, such as insulin resistance, dyslipidemia and lipodystrophy, have recently been described. This side effect may lead to premature coronary artery disease. Therefore it is mandatory to be aware that treatment with protease inhibitors in HIV-positive patients, despite survival prolongation and lowering of AIDS complications, may accelerate atherosclerosis and precipitate acute coronary events, especially in patients with pre-existing cardiovascular risk factors.