Abstract #1306

Tracking Edema, Hemorrhage and Microvascular Obstruction by MRI After Acute Myocardial Infarction

Nilesh R. Ghugre¹, Venkat Ramanan¹, Mihaela Pop², Yuesong Yang¹, Jennifer Barry¹, Beiping Qiang¹, Kim Connelly³, Alexander J. Dick¹, Graham A. Wright^1,2

¹Imaging Research, Sunnybrook Health Sciences Centre, Toronto, ON, Canada; ²Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada; ³Division of Cardiology, St. Michael's Hospital, Toronto, ON, Canada

Pathophysiological responses after acute myocardial infarction (AMI) include edema, hemorrhage and microvascular obstruction (MVO) along with cellular damage. The in vivo evolution of these processes throughout infarct healing has not been well characterized. The purpose of our study was to monitor the time course of edema (T2), hemorrhage (T2*) and MVO in porcine myocardium following AMI and to observe the relative resolution of these pathophysiological mechanisms. Our study suggests that quantitative T2 and T2* mapping techniques are potentially more specific than intensity measures in single images, allowing regional, longitudinal and cross-subject comparisons. Such in vivo characterization will be important in grading severity and evaluating treatment strategies in AMI, potentially improving clinical outcome.