A new study published in Mayo Clinical Proceedings indicates that the rate of acute myocardial infarction among pregnant women increased between 2002–2003 and 2012–2013 (7.1 per 100,000 hospitalisations vs. 9.5% per 100,000 hospitalisations; p<0.01 for trend) and this coincides with an increase in mean age at hospitalisation for labour and delivery. Furthermore, the study confirms previous findings that advanced maternal age is associated with a higher risk of acute myocardial infarction. Study author Sripal Bangalore (Leon H Charney Division of Cardiology, Department of Medicine, NYU School of Medicine, New York, USA) speaks to Cardiovascular News about the research.
Overall, what was incidence of acute myocardial infarction among pregnant women?
The incidence was around eight cases per 100,000 hospitalisations in pregnant women.
Why was it important to evaluate the incidence of acute myocardial infarction among pregnant women?
Although the incidence is low, it is important to recognise that the in-hospital mortality in such women with acute myocardial infarction is about 5%. This figure is devastating, particularly given the baby’s life is also at risk.
Why do you think the incidence of acute myocardial infarction has increased over time?
This may be due to the fact that more and more women are becoming pregnant at a later age (i.e. 30s and 40s vs. 20s). Additionally, more women with risk factors for myocardial infarction are becoming pregnant.
Why is there a link between increased maternal age and increased risk of acute myocardial infarction given that even “geriatric” mothers are still relatively young to be having an acute myocardial infarction?
Older age during pregnancy may be associated with many of the traditional risk factors for heart disease, such as hypertension, diabetes, and dyslipidaemia. Also, the physiological stress of pregnancy may have a greater impact on older women than in younger woman.
As to be expected, mortality was increased in pregnant women who had an acute myocardial infarction compared with pregnant women who did not have acute myocardial infarction. But, how did the mortality rates compare with non-pregnant acute myocardial infarction patients.
We did not directly compare mortality rates in pregnant women with an acute myocardial infarction vs. those in non-pregnant people with an acute myocardial infarction. However, in terms of the age groups we are referring to in our study, the rate of mortality associated with acute myocardial infarction was higher than that seen in non-pregnant individuals (in other studies).
How should acute myocardial infarction be managed in pregnancy?
Recognition of myocardial infarction is the first and most important step. There are challenges in the management of acute myocardial infarction in this cohort given the issues with bleeding associated with anticoagulation. Moreover, the pathophysiology of acute myocardial infarction may be different with a probable higher incidence of spontaneous coronary dissection (where management is less well defined).
If PCI with drug-eluting stents is performed, what needs to be considered when prescribing dual antiplatelet therapy (DAPT)?
The risk of bleeding immediately after childbirth should be considered—particularly as the safety of DAPT in lactating women is not known.
What steps can be taken to reduce the risk of acute myocardial infarction in pregnant women?
They key steps are to increase awareness among pregnant women about the risk of myocardial infarction and the need to control risk factors (such as diabetes, hypertension, and hyperlipidaemia) in those who have them. Also, a multidisciplinary approach between a cardiologist and obstetrician is needed for pregnant women who present with an acute myocardial infarction.
Further studies are needed to better define risks, management strategies, and treatment options.