Quantitative analysis of myocardial perfusion and regional left ventricular function from contrast-enhanced power modulation images

Our goal was to test the feasibility of using power modulation, a new echocardiographic imaging technique, for combined quantitative assessment of myocardial perfusion and regional LV function. Coronary balloon occlusions were performed in 18 anesthetized pigs. Images were obtained during iv contrast infusion at baseline, during coronary occlusion and reperfusion, and analyzed using custom software. At each phase, regional myocardial perfusion was assessed by calculating mean pixel intensity and the rate of contrast replenishment following high-power ultrasound impulses. LV function was assessed by calculating regional fractional area change. All ischemic episodes caused delectable and reversible changes in perfusion and function. Perfusion defects were visualized in real time and confirmed by a significant decrease in pixel intensity in the LAD territory following balloon inflation and reduced rate of contrast replenishment. Fractional area change significantly decreased in ischemic segments, and was restored with reperfusion. Power modulation allows simultaneous on-line assessment of myocardial perfusion and regional LV wall motion.