[The classic exercise test or by imaging? New applications of Doppler echocardiography]

Classic electrocardiographic exercise test was for many years the only stress modality to exercise the heart, and remains the most widely performed method for provoking ischemia. ST segment deviation on the ECG is the most often utilized marker of abnormal regional myocardial perfusion. But it has traditionally been considered to possess unsatisfactory accuracy in certain categories of patients, namely those with baseline ECG changes that preclude the diagnosis of coronary artery disease. To overcome these limitations, other stress modalities have been introduced recently, namely the radionuclide techniques like stress thallium or MIBI scintigraphy, utilizing inhomogeneous uptake of the radionuclide as a marker of abnormal regional myocardial perfusion, and represents a major improvement in diagnostic accuracy compared with exercise ECG. But these stress modalities are very expensive, and need radiation exposure. More recently stress echocardiography has been introduced and recommended by the American College of Cardiology as a valid and clinically useful technique, presenting several advantages over the radionuclide techniques: a relatively inexpensive test, provides immediate results, no radiation exposure. Because many patients cannot perform dynamic exercise, pharmacological stress testing (dipyridamole, adenosine, dobutamine) coupled with imaging techniques, in particular echocardiography has become very popular with high sensitivity and specificity for the non invasive diagnosis of coronary artery disease. The analysis of the results obtained from several studies, showed that these new stress modalities, are ready for routine clinical use.