Mean myocardial velocity mapping in quantifying regional myocardial contractile reserve in patients with impaired left ventricular systolic function:Doppler myocardial imaging study

The aim of this study was to use Doppler myocardial imaging-derived mean my ocardial velocity (MMV) at baseline and during low-dose dobutamine stress e chocardiography (DSE) to quantify regional contractile reserve of the left ventricle (LV). Sixteen patients (mean age 59 +/- 7 years) with coronary ar tery disease and regional left ventricular wall motion abnormalities were s tudied. During each increment of Dobutamine infusion, 6 2-dimensional trans thoracic apical images were acquired in standard gray-scale and Doppler myo cardial imaging modes at 30 degrees steps over 180 degrees. For the analysi s, the LV was divided into 18 segments. For each segment, both wall motion score and MMV obtained in systole and both early and late diastole were mea sured at baseline and at each stage of DSE. In viable segments by wall moti on score, MMV increased during DSE in systole and in early and late diastol e. In contrast, in nonviable segments, MMV did not change during DSE, Mean myocardial velocity mapping is a promising new approach to quantify regiona l myocardial contractile reserve of the LV.