Native T-1 Mapping by 3-T CMR Imaging for Characterization of Chronic Myocardial Infarctions

作者：Kali Avinash; Choi Eui Young; Sharif Behzad; Kim Young Jin; Bi Xiaoming; Spottiswoode Bruce; Cokic Ivan; Yang Hsin Jung; Tighiouart Mourad; Conte Antonio Hernandez; Li Debiao; Berman Daniel S; Choi Byoung Wook; Chang Hyuk Jae^*; Dharmakumar Rohan

来源：JACC: Cardiovascular Imaging , 2015, 8(9): 1019-1030.

DOI：10.1016/j.jcmg.2015.04.018

• chronic myocardial infarction
• native T-1 mapping
• viability imaging

OBJECTIVES The purpose of this study was to investigate whether native T-1 maps at 3-T can reliably characterize chronic myocardial infarctions (MIs) in patients with prior ST-segment elevation myocardial infarction (STEMI) or non-ST-segment elevation myocardial infarction (NSTEMI).
BACKGROUND Late gadolinium enhancement (LGE) cardiac magnetic resonance is the gold standard for characterizing chronic MIs, but it is contraindicated in patients with end-stage chronic kidney disease.
METHODS Native T-1 and LGE images were acquired at 3-T in patients with prior STEMI (n =13) and NSTEMI (n =12) at a median of 13.6 years post-MI. Infarct Location, size, and transmurality were measured using mean +/- 5 SDs thresholding criterion from LGE images and T-1 maps and compared against one another. Independent reviewers assessed visual conspicuity of MIs on LGE images and T-1 maps.
RESULTS Native T-1 maps and LGE images were not different for measuring infarct size (STEMI: p = 0.46; NSTEMI: p = 0.27) and transmurality (STEMI: p = 0.13; NSTEMI: p = 0.21) using thresholding criterion. Using thresholding criterion, good agreement was observed between LGE images and T-1 maps for measuring infarct size (STEMI: bias = 0.6 +/- 3.1%; R-2 = 0.93; NSTEMI: bias = -0.4 +/- 4.4%; R-2 = 0.85) and transmurality (STEMI: bias = 2.0 +/- 4.2%; R-2 = 0.89; NSTEMI: bias = -2.7 +/- 7.9%; R-2 = 0.68). Sensitivity and specificity of T-1 maps for detecting chronic Mls based on thresholding criterion were 89% and 98%, respectively (STEMI), and 87% and 95%, respectively (NSTEMI). Relative to LGE images, the mean visual conspicuity score for detecting chronic Mls was significantly Lower for T-1 maps (p < 0.001 for both cases). Median infarct-to-remote myocardium contrast-to-noise ratio was 2.5-fold higher for LGE images relative to T-1 maps (p < 0.001). Sensitivity and specificity of T-1 maps for visual detection were 60% and 86%, respectively (STEMI), and 64% and 91% (NSTEMI), respectively.
CONCLUSIONS Chronic Mls in STEMI and NSTEMI patients can be reliably characterized using threshold-based detection on native T-1 maps at 3-T. Visual detection of chronic Mls on native T-1 maps in both patient populations has high specificity, but modest sensitivity.

• 出版日期2015-9