Abstract 11579: Myocardial Infarction Size by 3D Reconstruction of Late Gadolinium Enhanced Magnetic Resonance Cardiac Imaging in the Mouse: Correlation With Left Ventricular (LV) Global and Regional Performance
Background: Assessment in vivo of murine myocardial infarction (MI) size, and its correlation with global and regional LV dysfunction, remains problematic. In this experimental MI model, the validity of 3-D reconstruction of late gadolinium enhanced (LGE) Bruker Biospec 7T magnetic resonance (MR) images was tested and compared to degree of LV dysfunction.
Methods and Results: Thirty-three male C57BL/6J mice were studied (Figure 1A). LGE MR images were obtained by FLASH-cine pulse sequence. Continuity 6 software was used to 3D reconstruct the LV from 1.0 mm contiguous 2D slices at end-diastole (Figure 1B) and -systole; wall motion was quantitated by 3D % shrinkage and regional surface area change (RSAC) at the endocardium. Hemodynamic assessment was followed post-mortem by histologic (TTC) measurement of infarction size. In the chronic MI study, control measurements were used for normalization of 3D parameters. Results are shown in Table 1. We found highly significant negative linear correlations between the absolute increase of max dP/dt, by dobutamine stimulation and LGE MI size at 2 days after MI in the acute (r=-0.83, P<0.0001) and at 4 weeks in the chronic MI (r=-0.77, P=0.0052) groups. 3D % RSAC measured at 2 days precisely predicted the ESV at 4 weeks (r=0.95, P<0.0001).
Conclusion: 3D reconstruction of LGE MR images quantitates MI size that correlates significantly with histologic infarct size, regional impairment of 3D shortening, endocardial surface area change, and LV global contractile reserve. This approach provides accurate end-points for interventions, pharmacologic and genomic, that potentially limit both direct and reperfusion injuries associated with acute MI.
Author Disclosures: C. Chao: None. Y. Gu: None. R. Bussell: None. W. Bradford: None. M. Hoshijima: None. K.L. Peterson: None.
- © 2015 by American Heart Association, Inc.