Pregnancy associated with increased MI risk, severity

Physiologic developments associated with pregnancy, including increased blood volume and hormonal changes, appear to increase both the risk and severity of acute myocardial infarction during pregnancy and as long as 3 months postpartum, according to research presented at the 61st Annual Scientific Session of the American College of Cardiology in Chicago, March 24-27.

Further, although most of the women did not present with hypertension, diabetes, or elevated cholesterol-risk factors commonly associated with cardiovascular disease-their heart attacks were more severe than those of nonpregnant women of the same age, and their mortality rate was 2 to 3 times higher.

The study, an extension of 2 studies performed by researchers at the University of Southern California Los Angeles, examined 150 new cases of pregnancy-associated heart attacks in the 6-year period since 2005. Only one-third of the women had atherosclerosis; more common among them was coronary dissection, in which layers of the arterial wall obstruct blood flow, a condition that rarely occurs outside of pregnancy. Use of guidelines for treating heart attacks in the general population may exacerbate coronary dissection, and the authors urge, "It is ... important to identify the cause of heart attack in pregnant women before deciding what therapies to use."

Elkayam U, Jalnapurkar S, Kealey A. Pregnancy associated myocardial infarction: contemporary experience in 150 cases between 2005 and 2011. Paper presented at: 61st Annual Scientific Session of the American College of Cardiology; March 25, 2012; Chicago, Illinois. Abstract 1174.