INCIDENCE, SIGNIFICANCE, AND MANAGEMENT OF EARLY BRADYARRHYTHMIA COMPLICATING ACUTE MYOCARDIAL INFARCTION

Abstract One result of the operation of a mobile coronary-care unit is that the proportion of patients seen early is greater than that recorded elsewhere. Thus among the initial 550 patients with myocardial infarction managed by the Belfast mobile unit, 400 (73%) came under intensive care within 4 hours. Bradyarrhythmia was found to be a remarkably frequent early complication. Posterior infarction was complicated by bradyarrhythmia in 61% of the patients who came under intensive care within 1 hour, and in 43% this dysrhythmia was present at the initial examination. It is suggested that excessive vagal discharge manifested by bradyarrhythmia is an important precursor of ventricular fibrillation and an important factor in the early high mortality from myocardial infarction. The use of atropine in the management of bradyarrhythmia is described, and its value in the correction of early acute heart-block is reported.