Association of Unrecognized Myocardial Infarction With Long-term Outcomes in Community-Dwelling Older Adults: The ICELAND MI Study
Acharya, T., Aspelund, T., Jonasson, T.F., Schelbert, E.B., Cao, J.J., Sathya, B., Dyke, C.K., Aletras, A.H., Sigurdsson, S., Thorgeirsson, G., Eiriksdottir, G., Harris, T., Launer, L.J., Gudnason, V., & Arai, A.E.
By Jonathan Scheiner, Research Assistant
The ICELAND MI Study has examined the long-term outcomes of unrecognized myocardial infarctions (MI) which is also known as silent heart attacks that were not detected at onset by clinicians due to lack of symptoms. Dr. Jane Cao, Director of Research and Cardiac Imaging at St. Francis Hospital is a member of this study group based at NIH. As many as 25% of all heart attacks are classified as silent heart attacks, only later detected by cardiovascular MRI, which has been shown to be more effective than electrocardiograms at identifying silent heart attack.
Within the ICELAND MI sample, 17% of all participants were found to have silent heart attacks , as detected by cardiovascular MRI, even higher than clinically recognized heart attacks (10%). By ten years, those with silent and clinically recognized heart attacks were found to have similar mortality rates, at 49% versus 51%: both significantly higher than in those with no heart attack (30%). The participants with silent heart attacks were also at significantly higher risk of heart failure than participants with no heart attack.
This study has shown that silent heart attack is a notably common and equally risky form of heart attack as compared to the recognized heart attack, This highlights the potential importance of early detection by cardiac MRI and clinical intervention to reduce the long-term risks of silent heart attack.