Bloqueios de ramo e bloqueios atrioventriculares como complicaçöes do infarto agudo do miocárdio na era trombolítica / Bundle branch and atrioventricular block as complications of acute myocardial infarction in the thrombolytic era

ABSTRACT

OBJECTIVE: To analyze the incidence of intraventricular and atrioventricular conduction defects associated with acute myocardial infarction and the degree of in hospital mortality resulting from this condition during the era of thrombolytic therapy. METHODS: Observational study of a cohort of 929 consecutive patients with acute myocardial infarction. Multivariate analysis by logistic regression. Was used. RESULTS: Logistic regression showed a greater incidence of bundle branch block in male sex (odds ratio = 1.87, 95 per cent CI = 1.02-3.42), age over 70 years (odds ratio = 2.31, 95 per cent CI = 1.68-5.00), anterior localization of the infarction (odds ratio = 1.93, 95 per cent CI = 1.03-3.65). There was a greater incidence of complete atrioventricular block in inferior infarcts (odds ratio = 2.59, 95 per cent CI 1.30-5.18) and the presence of cardiogenic shock (odds ratio = 3.90, 95 per cent CI = 1.43-10.65). Use of a thrombolytic agent was associated with a tendency toward a lower occurrence of bundle branch block (odds ratio = 0.68) and a greater occurrence of complete atrioventricular block (odds ratio = 1.44). The presence of bundle branch block (odds ratio = 2.45 95 per cent , CI = 1.14-5.28) and of complete atrioventricular block (odds ratio = 13.59, 95 per cent CI = 5.43-33.98) was associated with a high and independent probability of inhospital death. CONCLUSION: During the current era of thrombolytic therapy and in this population, intraventricular disturbances of electrical conduction and complete atrioventricular block were associated with a high and independent risk of inhospital death during acute myocardial infarction.