Liu Yumeng, Zhu Jingfen, Chen Meng, Wang Lingjie, Zhu Mo, Weng Zhen, Hu Chunhong
Department of Radiology, the First Affiliated Hospital of Soochow University, Suzhou, China.
MOE Engineering Center of Hematological Disease, Soochow University, Suzhou, China.
Ann Transl Med. 2022 Jul;10(14):794. doi: 10.21037/atm-22-3251.
Late gadolinium enhancement (LGE) by cardiac magnetic resonance (CMR) is useful for the detection of cardiac amyloidosis (CA), but characteristic LGE patterns do not always occur or they appear late in the disease. Native T1 and extracellular volume (ECV) by T1 mapping may improve disease detection and quantify myocardial amyloid load.
Thirty patients with definite CA, 10 patients with possible CA, 20 patients with hypertrophic cardiomyopathy (HCM) and 40 healthy volunteers were performed 3.0-T CMR including cine, pre- and postcontrast T1 mapping and LGE. Receiver-operating characteristic (ROC) curves were constructed to assess the diagnostic ability of native T1 and ECV for CA. Correlation analysis between native T1 or ECV and cardiac biomarkers, structure, and function indexes were assessed using Pearson or Spearman correlation, as appropriate.
Native T1 values were 1,429±93, 1,290±49, 1,304±42, and 1,225±21 ms, in definite CA, possible CA, HCM, and healthy controls, respectively. ECV values were 44%±9%, 34%±5%, 33%±4%, and 24%±3%, in definite CA, possible CA, HCM, and healthy controls, respectively. Native T1 [area under curve (AUC) =0.89, 95% confidence interval (CI): 0.75-1.00, P<0.001] and ECV (AUC =0.99, 95% CI: 0.98-1.00, P<0.001) showed good ability to differentiate LGE-negative patients with possible CA from healthy controls, especially ECV. Positive correlations were found between native T1 or ECV and New York Heart Association (NYHA) functional class (r=0.673 and r=0.594, respectively; P<0.001), NT-proBNP (r=0.668 and r=0.603, respectively; P<0.001), troponin T (r=0.724 and r=0.591, respectively; P<0.001), left ventricular (LV) mass index (r=0.668 and r=0.579, respectively; P<0.001), and global LV wall thickness (r=0.765 and r=0.629, respectively; P<0.001). Negative correlations were found between native T1 or ECV and left ventricular ejection fraction (LVEF) (r=-0.761 and r=-0.668, respectively; P<0.001) and left ventricular stroke volume (LVSV) (r=-0.777 and r=-0.729, respectively; P<0.001).
Native T1 and ECV, which are able to reflect cardiac biochemistry, structure, and function, have high diagnostic accuracy for detecting CA, especially in LGE-negative patients, and thus could be used for early diagnosis of CA.
心脏磁共振成像（CMR）的延迟钆增强（LGE）对心脏淀粉样变性（CA）的检测很有用，但特征性的LGE模式并不总是出现，或者在疾病后期才出现。通过T1映射获得的固有T1和细胞外容积（ECV）可能会改善疾病检测并量化心肌淀粉样蛋白负荷。
对30例确诊为CA的患者、10例可能患有CA的患者、20例肥厚型心肌病（HCM）患者和40名健康志愿者进行3.0-T CMR检查，包括电影成像、对比剂注射前后的T1映射和LGE。构建受试者操作特征（ROC）曲线以评估固有T1和ECV对CA的诊断能力。根据情况，使用Pearson或Spearman相关性评估固有T1或ECV与心脏生物标志物、结构和功能指标之间的相关性。
确诊为CA的患者、可能患有CA的患者、HCM患者和健康对照组的固有T1值分别为1429±93、1290±49、1304±42和1225±21毫秒；ECV值分别为44%±9%、34%±5%、33%±4%和24%±3%。固有T1[曲线下面积（AUC）=0.89，95%置信区间（CI）：0.75-1.00，P<0.001]和ECV（AUC =0.99，95%CI：0.98-1.00，P<0.001）显示出良好的能力，能够将可能患有CA的LGE阴性患者与健康对照组区分开来，尤其是ECV。在固有T1或ECV与纽约心脏协会（NYHA）心功能分级（分别为r=0.673和r=0.594；P<0.001）、N末端脑钠肽前体（NT-proBNP）（分别为r=0.668和r=0.603；P<0.001）、肌钙蛋白T（分别为r=0.724和r=0.591；P<0.001）、左心室（LV）质量指数（分别为r=0.668和r=0.579；P<0.001）以及左心室整体壁厚度（分别为r=0.765和r=0.629；P<0.001）之间发现了正相关。在固有T1或ECV与左心室射血分数（LVEF）（分别为r=-0.761和r=-0.668；P<0.001）以及左心室每搏输出量（LVSV）（分别为r=-0.777和r=-0.729；P<0.001）之间发现了负相关。
能够反映心脏生物化学、结构和功能的固有T1和ECV对CA的检测具有很高的诊断准确性，尤其是在LGE阴性患者中，因此可用于CA的早期诊断。
