Analysis of regional left ventricular function in the post-infarct mouse by magnetic resonance imaging with retrospective gating

摘要

Our aim was to test, in a murine myocardial infarction (MMI) model, the feasibility of a new MRI protocol with no ECG/respiratory gating, and compare normal mice versus MMI, in terms of global and regional LV function. A control group (C, 10 mice) and a MMI group (18 mice) were studied. MRI with retrospective gating was performed. End-diastolic (EDV) and end-systolic (ESV) LV volumes with ejection fraction (EF) were computed. In addition, regional fractional area change (RFAC) was used as index of regional wall motion. In MMI, LV size (in µL) was larger compared to C (EDV: 92±25 vs 36±4, ESV: 66±27 vs 10±3), with a significant decrease in EF (31±10 vs 72±7%). RFAC in C showed heterogeneous values. In MMI, RFAC decreased from LV base to apex, with a min (26%) in the anterior segment, in agreement with the occluded LAD. MRI with retrospective gating is feasible in mice, and regional LV function analysis allows the localization of the induced infarction.