Searching for the optimal strategy for the diagnosis of stable coronary artery disease. Cost-effectiveness of the new algorithm.

BACKGROUND Coronary arteriography is still widely accepted as a gold standard for the diagnosis of coronary artery disease (CAD), despite emerging methods such as multi-slice computed tomography. None of the presently available non-invasive diagnostic tests is perfect. The aim of the article was to make a comparison of the value and limitations of history, resting electrocardiography, exercise electrocardiography and dobutamine stress echocardiography in the diagnosis of CAD, and to create a simple algorithm for non-invasive diagnosis of CAD to optimize indications for coronarography. METHODS Prospective, multicentre trial. The collection of clinical data, resting electrocardiography, exercise treadmill electrocardiography, dobutamine stress echocardiography and catheterization data was performed on 600 patients with chest pain regarded as angina pectoris and no previous history of myocardial infarction. CAD was defined as >/= 50% narrowing of at least one major vessel. Final results were obtained in 551 patients, 65% male. The studied population was divided into three groups on the basis of pre-test likelihood of CAD: 1. high (> 70%), 2. intermediate (10-70%) and 3. low (< 10%). RESULTS Sensitivity and specificity of resting electrocardiography, exercise treadmill electrocardiography, dobutamine stress echocardiography and created algorithm were calculated: 23%, 87% and 93%, 21% and 85%, 69% and 96%, 44%, respectively. The prevalence of CAD in the studied population was 61%. CONCLUSIONS The diagnostic value of resting electrocardiography in stable CAD is low. Dobutamine echocardiography has comparable sensitivity but significantly higher specificity than exercise treadmill test. Our algorithm is simple, reasonably cost-effective and may be useful in decision making. When the probability of CAD is high, non-invasive testing is not indicated before coronary angiography; when it is intermediate or low, a first choice test should be different in female (stress echocardiography) and male (exercise electrocardiography). (Cardiol J 2007; 14: 544-551).