Prognostic implications of normal exercise tomographic thallium images in patients with angiographic evidence of significant coronary artery disease

This study examines the prognostic implications of normal exercise tomographic thallium images in medically treated patients with angiographic evidence of coronary artery disease (CAD). There were 97 patients aged 60 ± 10 years; 52 had 1-, 30 had 2-, and 15 had 3-vessel CAD (≥50% diameter stenosis). The exercise test was submaximal in 51 patients (53%); ST-segment depression during exercise occurred in 20 patients (21%), and angina during exercise occurred in 23 patients (24%). Most patients (71%) were receiving antianginal therapy. During a mean follow-up of 32 months, only 3 patients had cardiac events: 2 died of cardiac causes and 1 had nonfatal myocardial infarction (event rate 1.1%/year). None of those 3 patients had positive ST response during exercise. Thus, medically treated patients with CAD (including those with multivessel CAD) have a benign prognosis in the presence of normal exercise thallium images. These results have important implications in patient management and cost of health delivery.