Mental stress may trigger repeat heart attack

The team at Emory University investigated whether myocardial ischemia — when blood flow to the heart is reduced such that the heart muscle doesn’t get enough oxygen — induced by mental stress was associated with poor outcomes among heart attack survivors, and how this type of stress testing compares with conventional stress brought on by exercise.

Among more than 300 young and middle-aged individuals enrolled in the study, those who endured myocardial ischemia with mental stress had a two-fold higher likelihood of having another heart attack or dying from heart disease compared with those who did not have cardiac ischemia-induced by mental stress.

“In our study, myocardial ischemia provoked by mental stress was a better risk indicator than what we were able to see with conventional stress testing,” said Viola Vaccarino from Emory University’s Rollins School of Public Health in Atlanta and the study’s principal investigator. This is the only study of its kind in this relatively young adult population of heart attack survivors.

“These data point to the important effect that psychological stress can have on the heart and the prognosis of patients with heart disease,” she added. The investigators studied 306 adults aged 61 years or younger (50 years on average and range from 22-61 years), who had been in the hospital for a heart attack in the previous eight months. Traditional stress tests, in which someone exercises on a treadmill or takes a medicine that makes the heart beat faster and harder as if the person was exercising, have long been used to check blood flow to the heart and gauge the risk of heart problems. Taking into account patients’ psychological stress may help clinicians better evaluate the risk of recurrent heart attacks or death seen in some patients surviving a heart attack. Overall, mental stress-induced myocardial ischemia occurred in 16 per cent of patients and conventional ischemia in 35 per cent, suggesting that traditional ischemia due to exercise or drug-induced stress is more common.