New research demonstrates that magnetic resonance imaging can predict the risk of myocardial infarction or cardiac death in patients with coronary heart disease, according to a report in the October 15th rapid access issue of Circulation. Currently, some American centers use the technology to identify sites of stenosis in the coronary arterial system and to measure left ventricular ejection fraction, but the imaging technique has not been used as a predictive tool.

"This study is the first to determine that magnetic resonance imaging is a strong prognostic forecaster," said lead author W. Gregory Hundley, M.D. "Such information is important because it helps us identify which patients should receive more aggressive treatment."

Hundley's group examined 279 men and women referred for magnetic resonance imaging stress testing after ultrasound screenings were inconclusive. Hundley noted that the study yielded several important findings.

First, regardless of other risk factors, the imaging technique could predict fatal and nonfatal myocardial infarctions in patients with a left ventricular ejection fraction less than 66 percent of normal. In addition, the team found that patients whose damaged heart wall moves better at rest than when stressed also has an elevated risk for infarction.

Last, the investigators noted that the location of reduced blood flow or myocardial damage apparently influences risk. Reduced blood flow in the apex of the left ventricle indicated a higher risk.

"These findings have interesting implications," Hundley said. "Patients with isolated disease near the base and the middle of the ventricle often are referred for procedures to restore blood flow. This study suggests that in doing so, you might alleviate chest pain but not prevent a cardiac death."