3D perfusion mapping in the intact mouse heart after myocardial infarction using myocardial contrast echocardiography

摘要

An intact mouse model of surgically-induced myocardial infarction (MI) caused by permanent occlusion of the LeftAnterior Descending (LAD) coronary artery was studied. Normal mice with no occlusion were also studied ascontrols. For each mouse, contrast enhanced ultrasound images of the heart were acquired in parallel cross-sectionsperpendicular to the sternum at millimeter increments. For accurate 3D reconstruction, ECG gating and a tri-axialadjustable micromanipulator were used for temporal and spatial registration. Ultrasound images at steady-state ofblood refilling were color-coded in each slice to show relative perfusion. Myocardial perfusion defects and necrosiswere also examined postmortem by staining with Phthalo blue and TTC red dyes. Good correlation (R>0.93) inperfused area size was observed between in vivo measurements and histological staining. A 3D multi-slice model anda 3D rendering of perfusion distribution were created and showed a promising match with postmortem results, lendingfurther credence to its use as a more comprehensive and more reliable tool for in vivo assessment of myocardialperfusion than 2D tomographic analysis.