In Vivo Assessment of Rat Hearts with and without Myocardial Infarction by Cine NMR - Comparison of the NMR Method to Invasive Techniques and Application to Intervention Studies
Aim of the study was to test the feasibility of cine-NMR for assessment of the infarcted rat heart and to compare the results to established methods. Thereafter, the value of cine-NMR was tested in studies investigating interventions to change the course of the remodeling process. NMR was performed for determination of left ventricular (LV) volumes and mass, MI-size and cardiac output. After MRI rats underwent conventional hemodynamic measurements for determination of cardiac output and LV volumes by electromagnetic flowmeter and pressure-volume curves. LV wet weight was determined. MI-size was determined by histology. MRIacquired MI-size (18.5±2%) was smaller than histology (22.8±2.5%, p<0.05) with close correlation (r=0.97). There was agreement in LV mass between MRI and wet weight (r=0.97, p<0.05) and in the MRI- and flowmeter measurements of cardiac output (r=0.80, p<0.05). Volume by MRI differed from pressure-volume curves with good correlation (r=0.96, p<0.05). In conclusion, cine-NMR is a valuable diagnostic tool applicable to the rat model of MI. Being non-invasive and exact it offers new insights in the remodeling process after MI because serial measurements are possible.
KeywordsNuclear Magnetic Resonance Left Ventricular Volume Left Ventricular Remodel Electromagnetic Flowmeter Valuable Diagnostic Tool
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