EXERCISE ECHOCARDIOGRAPHY: ADVANTAGES AND DISADVANTAGES
Maria Prokudina, M.D., Ph.D., Federal North-West Medical Research Center, St. Petersburg, Russia
The presentation will describe the advantages and disadvantages of exercise echocardiography (Ex Echo) for evaluation of coronary artery disease (CAD). Advantages and benefits of Ex Echo are the following:
1. Accuracy and availability;
2. Test is non-invasive (Ex Echo avoids the risks of invasive procedures) and inexpensive;
3. Ex Echo does not require the purchase, handling or disposal of radionuclides;
4. Ex Echo provides real-time global and regional information about the ventricles;
5. The resting echo also provides additional information about valvular disease, site and extent of MI, chamber dilatation, thrombi and aneurysm;
6. Ex Echo is convenient to clinical practice, it takes less time, can be scheduled immediately and can be scheduled any time during a day;
7. Stress echo requires minimal staff.
Disadvantages of stress echocardiography are the following:
A. Factors contributing to false positives: severe hypertension, cardiomyopathies (LV dysfunction of unknown etiology), idiopathic hypertrophic subaortic stenosis; left bundle branch block, arrhythmias, pacemaker; severe AI; insufficient level of exertion; reader is too sensitive to very mild hypokinesia and over-reading normally stiff segments.
B. Factors contributing to false negatives: single-vessel disease, normalization of wall motion abnormalities, extensive collaterals to occluded vessel, the influence of medications, resting wall motion abnormalities and technical problems.
Conclusion: In spite of some false-negative and false-positive tests accuracy of exercise echocardiography is high and it is an excellent tool for evaluation of CAD.