Nilesh R. Ghugre1, Venkat Ramanan1,
Mihaela Pop2, Yuesong Yang1, Jennifer Barry1,
Beiping Qiang1, Kim Connelly3, Alexander J. Dick1,
Graham A. Wright1,2
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
Coronary
vasodilatory dysfunction has been shown in infarcted as well as remote
myocardium in patients with acute coronary syndrome. Our study demonstrates
the utility of T2-based BOLD effect in probing regional and longitudinal
fluctuations in vasodilatory function in a porcine model of myocardial
infarction at 3T. T2 measurements were performed in remote and infarcted
myocardium at rest and after Dipyridamole-induced vasodilation (stress).
Experimental observations indicated that T2 at 3T offers greater sensitivity
towards detecting changes in myocardial oxygenation compared to 1.5T,
consistent with a two-compartment theoretical model. Stress-induced
vasodilatory response using quantitative T2 can help evaluate remote-zone
vascular function and potentially identity salvageable myocardium in the
infarct zone.