Myocardial Infarction in Pregnancy

Abstract

Myocardial infarction is a rare complication during pregnancy, with an estimated incidence of one in 10,000 pregnancies. Less than 100 cases have been reported. Pregnancy is associated with profound alterations in the maternal cardiovascular system, making pregnancy in the presence of maternal cardiac disease hazardous. Labour and delivery increase cardiovascular stress. Maternal mortality in pregnancies complicated by myocardial infarction is 35 percent. Delivery within two weeks of infarction, or reinfarction during pregnancy is associated with mortality as high as 50 percent. Perinatal mortality is related to maternal outcome.Clinical management of the pregnant woman with myocardial infarction should be multidisciplinary, involving input from obstetrics, cardiology, and anaesthesia. The goals of management are to decrease cardiac work, prevent extension of infarction, increase oxygenation, and prevent complications. During labour and delivery, adequate analgesia, preferably epidural, is essential. The mode of delivery is controversial, however most authors recommend that Caesarean section be reserved for obstetric indications, with assisted vaginal delivery to shorten the second stage of labour being the preferred method. Cardiac arrest in pregnancy is a rare event, but one for which physicians should be prepared. Perimortem Caesarean section to save the fetus should be considered if maternal resuscitation is unsuccessful. Early recognition of myocardial infarction will facilitate effective management, prevention of complications, and improvement in maternal and perinatal survival.