Prognostic importance of early exercise testing in men with suspected unstable coronary artery disease

In 276 men with suspected unstable coronary artery disease i.e. recurring chest pain of new onset, increasing symptoms of anginal chest pain in formerly stable angina pectoris or suspected non-Q-wave infarction, an exercise test was performed 2-7 days after admission. Coronary events i.e. cardiac death (N = 4), Q-wave infarction (N = 11) and coronary artery bypass grafting (N = 34), were registered during one year follow-up. The indication for bypass grafting was incapacitating angina pectoris despite medication, and suitable coronary anatomy. Stepwise multiple regression analysis showed that S-T segment depression and limiting chest pain were the most important prognostic parameters regarding coronary events. In patients with S-T segment depression greater than 0.1 mV or limiting chest pain (N = 94) the occurrence of Q-wave myocardial infarction or cardiac death was 10.6% (N = 10) compared to 2.8% (N = 5) in patients without these criteria (N = 182) (P less than 0.01). Coronary artery bypass graft surgery was performed in 33% (N = 31) of the group with S-T segment depression greater than 0.1 mV or limiting chest pain but in only 1.7% (N = 3) of the other patients (P less than 0.001). Thus, in patients with suspected unstable coronary artery disease, whose symptoms and signs of ischaemia are stabilized by medication, an exercise test can safely be performed after a few days ambulation in the ward. The early exercise test provides important prognostic information regarding the risk for severe coronary events within the next year.