Fan Zi-Yang, Lin Yan-Wei, Shi Ruo-Yang, Yu Ling-Zhan, Wu Rui, Yao Qiu-Ying, Wesemann Luke D, Hu Jiani, Liu Qi, Zhou Yan, Chen Sheng, Wu Lian-Ming
Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China.
Department of Rheumatology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China.
Eur Radiol. 2023 Jun;33(6):3897-3907. doi: 10.1007/s00330-022-09363-5. Epub 2023 Jan 4.
To measure creatine distribution in idiopathic inflammatory myopathy (IIM) patients' myocardial segments and investigate whether cardiovascular magnetic resonance (CMR) chemical exchange saturation transfer (CEST) creatine mapping can detect subclinical myocardial changes, CEST's ability was further compared with other conventional CMR mapping sequences.
Forty IIM patients (53.5 ± 10.5 years, 26 males) and eight healthy controls (35.4 ± 6 years, 5 males) underwent CMR scans on a 3.0-T MR scanner. Patients with IIM were further classified into two subgroups according to cardiac troponin T (cTn-T) values: the elevated cTn-T subgroup (n = 14) and the normal cTn-T subgroup (n = 26). Cine imaging, T2 SPAIR, LGE imaging, T1 mapping, T2 mapping, and Cr (creatine) CEST were performed.
Cr mapping showed significantly reduced creatine in IIM patients among global myocardium (IIM: 0.109 ± 0.063, controls: 0.121 ± 0.021, p < 0.05), and decreased creatine signals were detected in all 16 cardiac segments (p < 0.05). Patients also had significantly prolonged native T1 and decreased enhanced T1 values in each cardiac segment (p < 0.05). There was no significant difference of LVEF and T2 values between IIM patients and controls. Between the two subgroups, elevated cTn-T was linked with creatine and extracellular volume fraction (ECV) values, providing a global average creatine signal of 0.107 vs 0.112 (p < 0.05) and 24.7 vs 32.4 (p < 0.05).
Creatine CEST mapping can detect early-stage heart involvement with negative LGE findings in IIM. Compared with T1 mapping, CEST provides increased sensitivity to ECV measurement, making it significantly better than T1, and a promising CMR sequence for screening subclinical myocardial damage.
• IIM patients with potential or ongoing heart involvement, elevated ECV, and reduced Cr CEST values could provide valuable information. • ECV and Cr CEST values were closely related to elevated cTn-T.
测量特发性炎性肌病（IIM）患者心肌节段中的肌酸分布，并研究心血管磁共振（CMR）化学交换饱和转移（CEST）肌酸成像是否能检测到亚临床心肌变化，进一步将CEST的能力与其他传统CMR成像序列进行比较。
40例IIM患者（年龄53.5±10.5岁，男性26例）和8名健康对照者（年龄35.4±6岁，男性5例）在3.0-T MR扫描仪上接受CMR扫描。IIM患者根据心肌肌钙蛋白T（cTn-T）值进一步分为两个亚组：cTn-T升高亚组（n = 14）和cTn-T正常亚组（n = 26）。进行电影成像、T2 SPAIR、延迟强化成像、T1成像、T2成像和Cr（肌酸）CEST成像。
Cr成像显示IIM患者全心肌中的肌酸显著降低（IIM：0.109±0.063，对照组：0.121±0.021，p<0.05），并且在所有16个心脏节段中均检测到肌酸信号降低（p<0.05）。患者每个心脏节段的固有T1也显著延长，强化T1值降低（p<0.05）。IIM患者与对照组之间的左心室射血分数（LVEF）和T2值无显著差异。在两个亚组之间，cTn-T升高与肌酸和细胞外容积分数（ECV）值相关，整体平均肌酸信号分别为0.107和0.112（p<0.05），ECV分别为24.7和32.4（p<0.05）。
肌酸CEST成像可在IIM患者中检测到LGE结果为阴性的早期心脏受累情况。与T1成像相比，CEST对ECV测量的敏感性更高，明显优于T1成像，是筛查亚临床心肌损伤的有前景的CMR序列。
• 有潜在或正在发生心脏受累、ECV升高和Cr CEST值降低的IIM患者可提供有价值的信息。• ECV和Cr CEST值与cTn-T升高密切相关。
