Bulluck Heerajnarain, Hammond-Haley Matthew, Fontana Marianna, Knight Daniel S, Sirker Alex, Herrey Anna S, Manisty Charlotte, Kellman Peter, Moon James C, Hausenloy Derek J
The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, University College London, London, UK.
National Amyloidosis Centre, University College London, Royal Free Hospital, London, UK.
J Cardiovasc Magn Reson. 2017 Aug 1;19(1):57. doi: 10.1186/s12968-017-0370-6.
A comprehensive cardiovascular magnetic resonance (CMR) in reperfused ST-segment myocardial infarction (STEMI) patients can be challenging to perform and can be time-consuming. We aimed to investigate whether native T1-mapping can accurately delineate the edema-based area-at-risk (AAR) and post-contrast T1-mapping and synthetic late gadolinium (LGE) images can quantify MI size at 1.5 T. Conventional LGE imaging and T2-mapping could then be omitted, thereby shortening the scan duration.
Twenty-eight STEMI patients underwent a CMR scan at 1.5 T, 3 ± 1 days following primary percutaneous coronary intervention. The AAR was quantified using both native T1 and T2-mapping. MI size was quantified using conventional LGE, post-contrast T1-mapping and synthetic magnitude-reconstructed inversion recovery (MagIR) LGE and synthetic phase-sensitive inversion recovery (PSIR) LGE, derived from the post-contrast T1 maps.
Native T1-mapping performed as well as T2-mapping in delineating the AAR (41.6 ± 11.9% of the left ventricle [% LV] versus 41.7 ± 12.2% LV, P = 0.72; R 0.97; ICC 0.986 (0.969-0.993); bias -0.1 ± 4.2% LV). There were excellent correlation and inter-method agreement with no bias, between MI size by conventional LGE, synthetic MagIR LGE (bias 0.2 ± 2.2%LV, P = 0.35), synthetic PSIR LGE (bias 0.4 ± 2.2% LV, P = 0.060) and post-contrast T1-mapping (bias 0.3 ± 1.8% LV, P = 0.10). The mean scan duration was 58 ± 4 min. Not performing T2 mapping (6 ± 1 min) and conventional LGE (10 ± 1 min) would shorten the CMR study by 15-20 min.
T1-mapping can accurately quantify both the edema-based AAR (using native T1 maps) and acute MI size (using post-contrast T1 maps) in STEMI patients without major cardiovascular risk factors. This approach would shorten the duration of a comprehensive CMR study without significantly compromising on data acquisition and would obviate the need to perform T2 maps and LGE imaging.
对再灌注 ST 段抬高型心肌梗死（STEMI）患者进行全面的心血管磁共振（CMR）检查可能具有挑战性且耗时。我们旨在研究在 1.5T 场强下，基于 T1 弛豫时间的心肌水肿危险区（AAR）是否可以通过 T1 加权成像准确界定，以及对比剂增强后的 T1 加权成像和合成延迟钆增强（LGE）图像是否可以量化心肌梗死面积。这样就可以省略传统的 LGE 成像和 T2 加权成像，从而缩短扫描时间。
28 例 STEMI 患者在接受直接经皮冠状动脉介入治疗后 3±1 天，接受了 1.5T 场强的 CMR 扫描。使用 T1 加权成像和 T2 加权成像对 AAR 进行量化。使用传统的 LGE 成像、对比剂增强后的 T1 加权成像以及从对比剂增强后的 T1 加权图像中衍生出的合成幅度重建反转恢复（MagIR）LGE 和合成相位敏感反转恢复（PSIR）LGE 对心肌梗死面积进行量化。
在界定 AAR 方面，基于 T1 弛豫时间的心肌水肿危险区（AAR）与 T2 加权成像表现相当（分别为左心室的 41.6±11.9%和 41.7±12.2%，P = 0.72；R = 0.97；组内相关系数 ICC = 0.986（0.969 - 0.993）；偏差为 -0.1±4.2%左心室）。传统 LGE 成像、合成 MagIR LGE（偏差 0.2±2.2%左心室，P = 0.35）、合成 PSIR LGE（偏差 0.4±2.2%左心室，P = 0.060）和对比剂增强后的 T1 加权成像（偏差 0.3±1.8%左心室，P = 0.10）在量化心肌梗死面积方面具有极好的相关性和方法间一致性，且无偏差。平均扫描时间为 58±4 分钟。不进行 T2 加权成像（6±1 分钟）和传统 LGE 成像（10±1 分钟）可将 CMR 检查时间缩短 15 - 20 分钟。
对于无重大心血管危险因素的 STEMI 患者，T1 加权成像可以准确量化基于水肿的 AAR（使用 T1 加权图像）和急性心肌梗死面积（使用对比剂增强后的 T1 加权图像）。这种方法可以缩短全面 CMR 检查的时间，而不会显著影响数据采集，并且无需进行 T2 加权成像和 LGE 成像。
