UMEM Educational Pearls

Category: Cardiology

Title: non-obstructive CAD and women

Keywords: acute MI, MI, myocardial infarction, acute coronary syndrome, women (PubMed Search)

Posted: 10/23/2011 by Amal Mattu, MD
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"Women experience higher mortality rates and more adverse outcomes after acute MI than men, despite less obstructive CAD and plaque burden."(1)

How can this be explained? It turns out that women have more frequent coronary remodeling of vessels. "Remodeling" refers to the concept that as plaques grow, they tend grow into the vessel wall causing outward bulging of the wall, rather than growing into the vessel lumen. That means that standard coronary angiography and even stress testing often miss significant lesions because they only evaluate lumen obstruction....which is not directly reflective of plaque size/burden.

The net effect of the above is that women are more likely to have false negative stress tests and angiograms that appear to show non-significant occlusions. Until we have reliable tests that evaluate true plaque burden rather than just vessel occlusion, we can't completely rely on stress testing and angiography to rule out the the presence of significant plaques.

References

1. Della Rocca DG, Pepine CJ. What causes myocardial infarction in women without obstructive coronary artery disease? Circulation 2011;124:1404-1406.

2. Reynolds HR, Srichai MB, Iqbal SN, et al. Mechanisms of myocardial infarction in women without angiographically obstructive coronary artery disease. Circulation 2011;124:1414-1425.