Implications of alternative strategies to diagnose coronary artery disease.

Strategies to diagnose coronary artery disease were examined for cost-effectiveness in a hypothetical population of 55-year-old men who, alternatively, are asymptomatic, have atypical angina or have definite angina. Strategies considered include various combinations of noninvasive tests (resting ECG, exercise stress test [ETT]. radionuclide scanning [RNS] and coronary angiography). Benefits are estimated in terms of the detection of multivessel disease and years of life gained from coronary artery bypass graft surgery (CABG). Only the direct costs (charges) for diagnostic or treatment procedures are considered. In asymptomatic persons, the average cost-effectiveness for different strategies ranges from $22,600 per year of life gained (ETT followed in positives by RNS) to $60,000 (angiography as primary screening test). Hence, screening is relatively cost-ineffective and would be extremely expensive if implemented widely. For patients with atypical angina, the cost-effectiveness ratio is about $9300 per year of life gained. Strategies involving use of ETT alone or in combination with the ECG or RNS appear to be preferable. For definite angina, the cost-effectiveness ratio is about $8800. Little difference is noted among various strategies for diagnosing definite angina, and the option to proceed directly to angiography appears reasonable.