Prophylactic Quinidine After Myocardial Infarction

It is widely accepted that the occurrence of myocardial infarction is becoming increasingly common. The mortality rate is high and the immediate causes of death include prolonged shock, cardiac rupture, congestive cardiac failure, pulmonary embolism, and cerebral embolism, all of which show clinical or post-mortem signs of their occurrence. In other cases death ensues during a recog- nized episode of cardiac arrhythmia or death may be sudden and unexplained. In a preliminary study of fatal cases of myocardial infarction (Begg, 1959, unpublished observations), approximately 25 per cent of the deaths were found to be sudden and unexplained by the clinical signs or autopsy findings. It is presumed that such deaths are due to cardiac arrhythmias, especially ventricular fibrillation, or perhaps to sudden cardiac arrest.