"Mental stress induced ischemia is more common than we had recognized," said David S. Sheps, M.D., M.S.P.H. from the University of Florida and the Malcom Randall Veterans Administration Medical Center in Gainesville, Florida. "It remains to be seen whether that ischemia is also associated in this population with an elevated risk for future health events, as it is in other populations."
The researchers, including lead author Srikanth Ramachandruni, M.D., monitored heart blood flow in 29 patients as they performed a mentally stressful role-playing scenario. All of the patients had coronary artery disease, but they had been treated and did not show any signs of ischemia (decreased heart muscle blood flow) on either treadmill tests or after an injection with a chemical that puts stress on heart blood flow. Mental stress has been shown to produce ischemia in heart disease patients who also have problems during exercise or chemical stress tests, but this is the first such study specifically designed to look at this broader group of patients.
The participants were asked to imagine a stressful situation, such as learning that a relative was being mistreated in a nursing home, and then give a short speech demonstrating how they would respond.
None of the patients felt chest pain or other symptoms of ischemia and there were no important differences in heart rate or blood pressure. But a minute into the speech, a radioactive tracer was injected into the patients. On the images then produced of blood flow in the heart muscle, six of the 29 patients showed signs of ischemia.