| Mental
stress can trigger cardiac ischemia and increase risk of death for
patients with coronary artery disease Mental stress can trigger cardiac ischemia and increase the risk of death in people with coronary artery disease, according to an article in the March 26th rapid access issue of Circulation. Previous studies had shown that reduced blood flow during mental stress tests is linked to significantly higher rates of adverse cardiac events, but these studies were not designed to detect differences in death rates. "Patients who had ischemia in response to mental stress had a three-fold increase in the risk of death compared to people without mental stress," says David S. Sheps, M.D., lead author. "This adds to a growing body of evidence that links mental stress and bad outcomes in individuals with coronary artery disease." The 196 patients in the current study - Psychophysiological Investigations of Myocardial Ischemia - had documented coronary artery disease and exercise-induced ischemia. Patients had a more than 50 percent narrowing in at least one major coronary artery or a previous myocardial infarction. Follow-up was done at 3.5 and 5.2 years. Patients were excluded if they had a serious noncardiac illness, unstable angina, neurological disease, were unable to discontinue medications that influence cardiac function, or had undergone coronary surgery or angioplasty. An exercise stress test, radionuclide imaging of the heart and a psychological stress test were conducted at the start of the study. In the psychological stress test patients were asked to talk for five minutes on an assigned topic. The topic required role-playing in which a close relative was being mistreated. The radionuclide test detected abnormalities during the speech test in 20 percent of patients. Patients with abnormalities were more often female (24 percent versus 12 percent) and more likely to have a history of diabetes (27 percent versus 12 percent). Patients with wall motion abnormalities during the speech test had a 2.8 times higher death rate than those without abnormalities. All of the 17 deaths were men. Forty percent of those who died had new or worsened abnormalities during the speech test compared with 19 percent of the survivors. Sheps says prospective study is indicated. Research should focus on reproducing this finding and searching for an inexpensive technique for myocardial imaging that would make mental stress testing more attractive for routine clinical use. "It is important
to find out which patients are at risk and to learn ways to tailor
treatment to those at risk. It may be that we can alter the lifestyles
of people at risk and get them to respond differently to the stress,"
he says. |