Failure To Diagnose Heart Attacks Linked To Increased Risk Of Future Heart Problems: Study

According to the findings of new research, failure to diagnose a heart attack may lead to future heart problems down the road. 

Researchers from the U.S. and Iceland published a study this month in the medical journal JAMA Cardiology, indicating that long-term unrecognized myocardial infarction (UMI) was linked to an increased risk of heart failure and death. However, the findings also suggest that the death rates, while higher than among those who never suffered a heart attack, were about the same as those accurately diagnosed.

According to the findings, it is unclear how common undiagnosed heart attacks are, as the rate appears to change with various study populations and methods of detection used. What researchers do know is that there are more unrecognized heart attacks diagnosed by cardiovascular magnetic resonance imaging (CMR) than there are recognized heart attacks in older populations. Unrecognized myocardial infarction is also known to be linked to poor survival rates overall, the researchers indicated.

Researchers looked at data on 5,674 older Icelandic patients from January 2004 through January 2007. They looked for recognized myocardial infarction (RMI) supported by hospital records, and unrecognized heart attacks recognized by MRI scans and a consensus of cardiologists.

According to the findings, mortality rates among unrecognized heart attack victims were 13% after five years, compared to only 8% among those who had suffered no heart attacks. By 10 years the mortality rate among unrecognized and recognized myocardial infarction were 49% and 51% respectively, considered statistically insignificant. However, both were much higher than the 30% rate among those who had never suffered a heart attack.

The researchers determined that those who had unrecognized heart attacks had a 61% higher risk of death, and a 52% higher risk of heart failure when compared to those with no history or myocardial infarction.

“In this study, all-cause mortality of UMI was higher than no MI, but within 10 years from baseline evaluation was equivalent with RMI,” the researchers concluded. “Unrecognized MI was also associated with an elevated risk of nonfatal MI and heart failure, Whether secondary prevention can alter the prognosis of UMI will require prospective testing.”