Abstract #3402

The Tractographic Propagation Angle: A Novel Tool to Detect Infarction & Characterize Myocardial Microstructure

Choukri Mekkaoui¹, Shuning Huang¹, Guangping Dai¹, Timothy G. Reese¹, Udo Hoffmann², Marcel P. Jackowski³, David Sosnovik⁴

¹Radiology, Harvard Medical School, Massachusetts General Hospital, Martinos Center For Biomedical Imaging, Charlestown, MA, United States; ²Radiology, Massachusetts General Hospital, Harvard Medical School, United States; ³Computer Science, University of So Paulo, Institute of Mathematics & Statistics, So Paulo, Brazil; ⁴Cardiology, Harvard Medical School, Massachusetts General Hospital, Martinos Center For Biomedical Imaging, Charlestown, MA, United States

The normal angle between adjacent eigenvectors along myofiber tracts remains unknown. We term this angle the tractographic propagation angle (PA). Consequently, the correct upper limit or threshold angle to use in tractographic reconstructions of the myocardium remains unknown. Here we characterize the propagation angle (PA) in vivo in normal and ex vivo in infarcted hearts. We show that PA is homogenous and low (2-4 degrees) in normal myocardium. In infarcted myocardium, PA rises dramatically and has the potential to facilitate the robust detection of myocardial infarcts.