[Auriculoventricular blocks in the acute phase of myocardial infarction. Course and prognosis. Apropos of 90 cases].

The objective is to study the clinical and electrocardiographic characteristics as well as the course of myocardial infarction complicated by atrio-ventricular block (AVB), and to propose a management to acute myocardial infarction with A-V block. This study concerns 90 patients (78 men and 12 women), with a mean age of 58 years. The overall frequency of AVB is 7.6 p. cent. The infarction is most of the time found posteriorly (51 p. cent of the cases). Syncopes are essentially seen in complete AVB (81 p. cent) and with deep antero-septal necrosis (73 p. cent). Heart failure is especially the complication of anterior (73 p. cent) and deep septal (78 p. cent) necrosis. The mortality of myocardial infarction complicated by A-V block (41 p. cent) is higher than that of uncomplicated necroses (15 p. cent). The prognosis is usually favorable in posteriorly located infarctions where the A-V block is usually regressive and benign while it is much more severe in other locations where the conduction disorders associated with severe myocardial lesions. Temporary and/or permanent electrosystolic stimulation must be well codified in its indications which should be broadened, especially in case of anterior or deep septal necrosis.