Clinical Use of Doppler Echocardiography and Doppler Tissue Imaging in the Estimation of Myocardial Ischemia During Dobutamine Stress Echocardiography

Abstract

The ratio of mitral inflow early diastolic velocity (E) to annulus velocity (E') might be critical for the assessment of an abnormal filling pressure for patients with myocardial ischemia. We sought to determine whether a quantitative estimation of E/E' provides more reliable information for detecting coronary artery disease during dobutamine stress echocardiography. A total of 82 patients suggested to have angina pectoris underwent Doppler studies during dobutamine stress echocardiography. The value of E and E' were measured at baseline and peak dose of dobutamine stress. The value of E/E' during stress over that at rest was defined as the E/E' index. Patients who had significant stenosis by coronary angiogram were classified as being in group A (n = 45) and those with no coronary artery disease were classified as being in group B (n = 37). Dobutamine infusion led to a significant increase of E/E' in group A, whereas no changes were found with group B. Likewise, larger E/E' index was also observed for patients with multivessel disease. The value of E/E' index increased proportionally with the number of stenotic vessels, implying a direct correlation of the E/E' value to the extent of myocardial ischemia. E/E' offers a quantitative estimation of myocardial ischemia during dobutamine stress echocardiography, thereby, providing a reliable and accurate method for the evaluation of coronary artery disease.