Rapid three-dimensional myocardial contrast echocardiography: Volumetric quantitation of nonperfused myocardium after intravenous contrast administration

Current acquisition methods for quantitative three-dimensional myocardial contrast echocardiography require long acquisition times and therefore require the invasive administration of deposit contrast agents administered intra-arterially or into the left atrium. This study addressed the feasibility of obtaining accurate and precise quantitative volumetric measurements of nonperfused myocardium after an intravenous bolus of echocardiographic contrast agent using a rapid three-dimensional myocardial contrast echocardiographic acquisition technique. An open-chest pig model of acute left anterior descending coronary artery (LAD) occlusion was used. After LAD ligature, an intravenous bolus of contrast agent was given and images were obtained over a 12-second period using a continuously rotating transducer placed at the apical position. There was no significant microbubble destruction during the rotational acquisition period as measured by differences in mean gray scale values of apical, mid, and basal myocardial regions between the first and last image frames of acquisition. Calculated volumes of nonperfused myocardium demonstrated significant agreement and correlation (mean difference ± SD = -0.30 ± 1.71 cm³; r = 0.89; P < 0.01; y = 1.06x - 1.08) with anatomic specimens. When expressed as percent of total LV volume being nonperfused, the mean difference ± SD was 2.1 ± 3.6%, r = 0.94, P < 0.01, and y = 1.33x - 4.08. We conclude that accurate and precise measurements of nonperfused myocardium after an acute LAD coronary artery occlusion can be obtained after the intravenous bolus administration of a contrast material when a rapid 12-second acquisition with a continuously rotating transducer is used.