Abstract 12805: Fast, Free-Breathing, Whole-Heart Cardiac Magnetic Resonance T2 Mapping for Myocardial Edema Imaging
Introduction: Cardiac MRI (CMR) T2 mapping is a proven method for myocardial edema detection. However, the current approach requires multiple breath-holds and can take nearly 10-15 minutes to complete. Faster acquisitions could potentially improve patient comfort and cost-effectiveness of CMR exams that benefit from T2 maps.
Objective: To develop and test a fast, free-breathing, three-dimensional, whole-heart T2 mapping for accurate imaging of myocardial edema against the standard (breath-held 2D) T2 maps following ischemia-reperfusion injury.
Methods: Ischemia-reperfusion injury was inflicted in canines (n=10) with 3 hours of no-flow ischemia followed by reperfusion. On day 4 post MI, proposed (fast 3D) T2 maps during free breathing with near perfect imaging efficiency, standard T2 maps and Late gadolinium enhancement (LGE) images were acquired using a clinical 3T system. Guided by LGE CMR, remote myocardium was identified on standard and proposed T2 maps and the 2SD-threshold criterion was used to characterize the infarcted regions for myocardial edema. Subsequently, T2 values of remote and infarcted regions were measured and the volume of edematous territories was estimated. Regression and Bland-Altman analysis were performed to examine the correspondence.
Results: Close correspondence between edematous territories in the slice-matched standard and proposed T2 maps was observed. T2 values were significantly elevated in regions positive for LGE in both T2 maps. Linear regression analysis showed that the T2 estimates (edematous and remote territories) and the % edema volume measured from both T2 maps were closely correlated (T2: R2 = 0.88 with 0.4 ms bias; %edema volume: R2 = 0.96 with 0.6% bias. Both p<0.05).
Conclusions: The proposed free-breathing, three-dimensional, whole-hreat T2 mapping approach at 3T can be performed within 5 minutes with an accuracy in T2 not different from that of the state-of-the-art breath-held T2 mapping approach.
Author Disclosures: H. Yang: None. B. Sharif: None. J. Pang: None. A. Kali: None. X. Bi: None. I. Cokic: None. D. Li: None. R. Dharmakumar: None.
- © 2014 by American Heart Association, Inc.