Doppler echocardiographic measurement of low velocity motion of the left ventricular posterior wall

Abstract

A new noninvasive method using pulsed Doppler echocardiography was developed to assess left ventricular (LV) posterior wall motion dynamics. Seventeen normal subjects and 23 patients undergoing cardiac catheterization were prospectively studied. The sample volume was placed within the LV posterior wall endocardium just apical to the mitral valve sulcus using a posteriorly angulated low parasternal view. The wall filter was set at 100 Hz to record the low velocities of the LV posterior wall motion. The Doppler signal was morphologically similar to the rate of change of the LV posterior wall endocardium excursion obtained by a digitized M-mode echocardiogram, and showed 3 major waves: a systolic wave (S), an early diastolic wave (E) and a late diastolic wave (A). The peak velocities of LV posterior wall endocardium excursion were also determined by M-mode echocardiographic technique. We found a significant linear correlation between peak E-wave velocity and M-mode peak diastolic endocardial velocity (r = 0.90, p less than 0.001) and between peak S-wave velocity and M-mode peak systolic endocardial velocity (r = 0.81, p less than 0.001). M-mode peak systolic endocardial velocity showed an important overlap between control subjects and patients with normal and patients with abnormal LV posterior wall motion on the angiogram. In contrast, peak S-wave velocity was a better discriminator, and a peak S-wave velocity less than 7.5 cm/s was associated with abnormal LV posterior wall motion with an 83% sensitivity, 100% specificity and 95% accuracy. In patients with coronary artery disease but normal systolic LV posterior wall motion and normal global systolic LV function, peak S-wave velocity was not different when compared to control subjects. Peak E-wave velocity and E/A were significantly lower than in control subjects (p less than 0.01) and peak A-wave velocity was greater (p less than 0.01). In conclusion, these data suggest that pulsed Doppler echocardiography can be used for the direct analysis of LV posterior wall instantaneous low velocities and appears to be more informative than M-mode technique for systolic measurements. Thus, detection of abnormal LV posterior wall diastolic motion by pulsed Doppler echocardiography may, upon additional confirmation, be used as a new noninvasive method to gain insight into global LV diastolic performance.