NEW YORK (Reuters Health) – Exercise echocardiography can predict mortality and major cardiac events in patients with known or suspected coronary artery disease, but who have normal exercise ECG results, new research indicates.

According to the report, new or worsening wall motion abnormalities on exercise echocardiography predicted a 2.73-fold increased risk of death and a 3.59-fold increased risk of major cardiac events.

Treadmill ECG testing looks for ST-segment changes with coronary disease, Dr. Alberto Bouzas-Mosquera, from Hospital Universitario A. Coruna, Spain, and colleagues note. However, prior research has shown that patients often manifest exercise-induced wall-motion abnormalities before such changes are apparent. Therefore, echocardiography may be able to provide prognostic information, when ECG cannot.

In the current study, the researchers attempted to answer this question by analyzing echocardiographic data from 4004 patients who had no chest pain or ischemic ECG abnormalities during exercise testing. The subjects were considered to have ischemia if new or worsening wall motion abnormalities were seen on exercise echocardiography.

The new findings are reported in the Journal of the American College of Cardiology for May 26.

Overall, 313 patients died and 183 had a major cardiac event during a mean follow-up period of 4.5 years, the authors note.

Almost 17% of patients had ischemia with exercise. The 5-year mortality rates in subjects with or without ischemia were 12.1% and 6.4%, respectively, while the corresponding major cardiac event rates wee 10.1% and 4.2% (p < 0.001). On multivariate analysis, the exercise echography results were confirmed as an independent predictor of both mortality and major cardiac events and adding the results to clinical, resting echocardiographic, and exercise hemodynamic data further improved the predictive model. In a related editorial, Dr. Frank A. Flachskampf and Dr. Christian Rost, from Med. Klinik 2, Erlangen, Germany, comment that the current study provides compelling support for “a larger role for imaging stress tests, in particular exercise stress echocardiography, in coronary risk stratification of patients with intermediate pre-test likelihood of coronary artery disease.” References:
J Am Coll Cardiol 2009;53:1981-1992.