4D cardiac imaging at clinical 3.0T provides accurate assessment of murine myocardial function and viability

摘要

AbstractObjectivesWe validate a 4D strategy tailored for 3T clinical systems to simultaneously quantify function and infarct size in wild type mice after ischemia/reperfusion, with improved spatial and temporal resolution by comparison to previous published protocols using clinical field MRI systems.MethodsC57BL/6J mice underwent 60min ischemia/reperfusion (n=14) or were controls without surgery (n=6). Twenty-four hours after surgery mice were imaged with gadolinium injection and sacrificed for post-mortem MRI and histology with serum also taken for Troponin I levels. The double ECG- and respiratory-triggered 3D FLASH (Fast Low Angle Shot) gradient echo (GRE) cine sequence had an acquired isotropic resolution of 344μm, TR/TE of 7.8/2.9ms and acquisition time 25–35min. The conventional 2D FLASH cine sequence had the same in-plane resolution of 344μm, 1mm slice thickness and TR/TE 11/5.4ms for an acquisition time of 20–25min plus 5min for planning. Left ventricle (LV) and right ventricle (RV) volumes were measured and functional parameters compared 2D to 3D, left to right and for inter and intra observer reproducibility. MRI infarct volume was compared to histology.ResultsFor the function evaluation, the 3D cine outperformed 2D cine for spatial and temporal resolution. Protocol time for the two methods was