Imaging Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
Department of Radiology, Department of Biomedical Engineering, University of Michigan, 1150 West Medical Center Drive, Ann Arbor, MI 48109, USA.
Int J Cardiol. 2022 Mar 15;351:107-110. doi: 10.1016/j.ijcard.2021.12.038. Epub 2021 Dec 25.
Cardiac amyloidosis (CA) is an infiltrative cardiomyopathy with poor prognosis absent appropriate treatment. Elevated native myocardial T and T have been reported for CA, and tissue characterization by cardiac MRI may expedite diagnosis and treatment. Cardiac Magnetic Resonance Fingerprinting (cMRF) has the potential to enable tissue characterization for CA through rapid, simultaneous T and T mapping. Furthermore, cMRF signal timecourses may provide additional information beyond myocardial T and T.
Nine CA patients and five controls were scanned at 3 T using a prospectively gated cMRF acquisition. Two cMRF-based analysis approaches were examined: (1) relaxometric-based linear discriminant analysis (LDA) using native T and T, and (2) signal timecourse-based LDA. The Fisher coefficient was used to compare the separability of patient and control groups from both approaches. Leave-two-out cross-validation was employed to evaluate the classification error rates of both approaches.
Elevated myocardial T and T was observed in patients vs controls (T: 1395 ± 121 vs 1240 ± 36.4 ms, p < 0.05; T: 36.8 ± 3.3 vs 31.8 ± 2.6 ms, p < 0.05). LDA scores were elevated in patients for relaxometric-based LDA (0.56 ± 0.28 vs 0.18 ± 0.13, p < 0.05) and timecourse-based LDA (0.97 ± 0.02 vs 0.02 ± 0.02, p < 0.05). The Fisher coefficient was greater for timecourse-based LDA (60.8) vs relaxometric-based LDA (1.6). Classification error rates were lower for timecourse-based LDA vs relaxometric-based LDA (12.6 ± 24.3 vs 22.5 ± 30.1%, p < 0.05).
These findings suggest that cMRF may be a valuable technique for the detection and characterization of CA. Analysis of cMRF signal timecourse data may improve tissue characterization as compared to analysis of native T and T alone.
心脏淀粉样变性（CA）是一种预后不良的浸润性心肌病，缺乏适当的治疗方法。已有研究报道 CA 患者的心肌固有 T1 和 T2 值升高，心脏 MRI 的组织特征分析可能有助于加速诊断和治疗。心脏磁共振指纹技术（cMRF）有可能通过快速、同时的 T1 和 T2 映射来实现 CA 的组织特征分析。此外，cMRF 信号时间曲线可能提供比心肌 T1 和 T2 更多的信息。
在 3T 上使用前瞻性门控 cMRF 采集对 9 例 CA 患者和 5 例对照者进行扫描。检查了两种基于 cMRF 的分析方法：（1）基于弛豫的线性判别分析（LDA），使用固有 T1 和 T2；（2）基于信号时间曲线的 LDA。采用 Fisher 系数比较两种方法对患者和对照组的可分离性。采用留二法交叉验证评估两种方法的分类错误率。
与对照组相比，患者的心肌 T1 和 T2 值升高（T1：1395±121 比 1240±36.4 ms，p<0.05；T2：36.8±3.3 比 31.8±2.6 ms，p<0.05）。基于弛豫的 LDA（0.56±0.28 比 0.18±0.13，p<0.05）和基于信号时间曲线的 LDA（0.97±0.02 比 0.02±0.02，p<0.05）的 LDA 评分在患者中升高。基于信号时间曲线的 LDA 的 Fisher 系数大于基于弛豫的 LDA（60.8 比 1.6）。基于信号时间曲线的 LDA 的分类错误率低于基于弛豫的 LDA（12.6%±24.3 比 22.5%±30.1%，p<0.05）。
这些发现表明，cMRF 可能是检测和特征分析 CA 的一种有价值的技术。与单独分析固有 T1 和 T2 相比，分析 cMRF 信号时间曲线数据可能会改善组织特征分析。
