Maria das Graças Viana Pinheiro et al. Alvaro Rabelo Jr. Rogerio Santos de Jesus Luciana Cunha Nascimento Ursula Maria Moreira Costa
OBJECTIVE: To assess the clinical characteristics, evolution, and in-hospital complications of patients with acute coronary syndromes (ACS) in the absence of significant obstructive coronary artery disease (CAD). METHODS: Cross-sectional study of patients hospitalized from August 1996 to March 2002 with acute coronary syndrome, with or without an elevation in the ST segment, and with (= 50%) or without (<50%) significant coronary stenosis. Their clinical and demographic characteristics and their in-hospital complications were analyzed. RESULTS: Of the 1351 patients admitted with acute coronary syndrome, 28% had an elevation in the ST segment and 72% had no elevation. The patients with acute coronary syndrome with no elevation in the ST segment and no significant coronary obstruction were younger, predominantly females, and had a lower frequency of dyslipidemia, previous coronary arterial disease, diabetes mellitus, smoking, and systemic arterial hypertension, when compared with those with significant obstructive lesion. Among the individuals with acute coronary syndrome and an elevation in the ST segment, smoking was the most prevalent risk factor in patients with nonsignificant obstructive lesion. In regard to complications, recurring ischemia, congestive heart failure, and arrhythmias were more frequent in patients with acute coronary syndrome with no elevation in the ST segment and no significant obstructive coronary lesion. CONCLUSION: Patients with acute coronary syndrome with no elevation in the ST segment and with nonsignificant obstructive coronary lesions are younger, predominantly females, have a greater frequency of risk factors for coronary arterial disease, and a lower incidence of complications as compared with patients with significant obstructive coronary lesion.