Stress echocardiography for the diagnosis of coronary artery disease: progress towards quantification

PURPOSE OF REVIEW: This review highlights recent progress in the quantitative approach to the interpretation of stress echocardiograms. Recent literature regarding the application of tissue Doppler and strain rate imaging for the diagnosis of coronary artery disease is summarized. RECENT FINDINGS: The high temporal and spatial resolution of tissue Doppler and strain rate imaging permit recognition of regional myocardial dysfunction. These techniques have been performed during low- and high-dose dobutamine stress echocardiography and have been applied to exercise echocardiography. During stress, the peak systolic velocity and early diastolic velocity increased to a greater degree in normal segments compared to ischemic segments. With tissue Doppler imaging, viable segments show increases in systolic velocities in contrast to infarcted segments. Presently, the feasibility of strain rate imaging is slightly less than that of conventional wall motion assessment. However, in preliminary studies, tissue Doppler parameters and especially strain rate parameters appear to offer advantages in accuracy compared to conventional wall motion assessment. SUMMARY: Tissue Doppler and strain rate imaging offer great promise for the accurate, reproducible quantification of regional myocardial function. Further studies are indicated to prove their accuracy, efficiency, and superiority over existing methods.