Unrecognized Heart Attacks are as Serious as Recognized Ones

If you had a “silent” heart attack and didn’t know it, does it matter?

Tushar Acharya, MD, and colleagues of the National Heart, Lung, Blood Institute of the National Institutes of Health, called unrecognized myocardial infarctions (MI) “an underappreciated public health problem.” The research team found that the combined risk of death, a subsequent nonfatal heart attack, and heart failure were similar at a 10-year follow up for both recognized and unrecognized MI. The unrecognized MIs were identified using cardiac magnetic resonance (CMR).

CMR identifies smaller MIs than are detectable by electrocardiography. Patients with unrecognized, smaller MIs have less heart muscle damage and better heart function than people with recognized MIs. However, due to non-recognition of MI, they are less likely to receive guidelines-directed medical therapy and modify lifestyle risk factors, such as smoking, said Dr. Acharya, an assistant professor of medicine, Division of Cardiology, Department of Medicine and Sarver Heart Center at the University of Arizona College of Medicine – Tucson.

“Whether early detection of unrecognized MI by CMR could allow for better risk factor management and thus reduce the associated long-term risk merits further investigation,” said Dr. Acharya. “Population screening to identify MI using CMR may not be cost-effective or practical at this time, however broader use of CMR in patients with heart disease could detect many more heart attacks than an ECG.”

The study, “Association of Unrecognized Myocardial Infarction With Long-term Outcomes in Community-Dwelling Older Adults: The ICELAND MI Study,” was published Oct. 10, 2018, in JAMA Cardiology. The study included 935 men and women, aged 67 to 93 years, in Reykjavik, Iceland, who underwent CMR at baseline and were followed for up to 13.3 years. The National Institutes of Health, the Icelandic Heart Association, and the Icelandic Parliament funded this study.