Division of Pediatric Cardiology, Children's Hospital Colorado, Heart Institute, University of Colorado Denver, Anschutz Medical Campus, 13123 E 16th Ave, Aurora, CO, USA.
Division of Cardiothoracic Surgery, Children's Hospital Colorado, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA.
Sci Rep. 2023 Jul 24;13(1):11912. doi: 10.1038/s41598-023-39226-y.
Myocardial deformation analysis by cardiac MRI (CMR) yielding global circumferential and longitudinal strain (GCS and GLS) is an increasingly utilized method to accurately quantify systolic function and predict clinical events in patients with Fontan circulation. The purpose of this study was to use principal component analysis (PCA) to investigate myocardial temporal deformation patterns derived from strain-time curves to learn about latent strain features beyond peak values. We conducted the study with specific attention to dominant single left or right ventricle (SLV and SRV) morphologies. Methods and Results: Patients remote from Fontan operation who underwent follow-up CMR were analyzed for standard volumetric and function hemodynamics including myocardial deformation parameters including GCS and GLS. We applied PCA to investigate in an unbiased fashion the strain-time curve morphology and to calculate patient specific shape scores. All variables were subjected to single variable Cox regression analysis to detect composite clinical outcome including death, heart transplant, protein losing enteropathy and plastic bronchitis. A total of 122 patients, (SLV = 67, SRV = 55) with a mean age of 12.7 years underwent comprehensive CMR analysis. The PCA revealed 3 primary modes of strain-curve variation regardless of single ventricle morphology and type of strain investigated. Principle components (PCs) described changes in (1) strain-time curve amplitude, (2) time-to-peak strain, and (3) post-systolic slope of the strain-time curve. Considering only SLV patients, GCS was only CMR variable predictive of clinical events (HR 1.46, p = 0.020). In the SRV group, significant CMR predictors of clinical events were derived indexed end-diastolic (HR 1.02, p = 0.023) and end-systolic (HR 1.03, p = 0.022) volumes, GCS (HR 1.91, p = 0.003) and its related first component score (HR 1.20, p = 0.005), GLS (HR 1.32, p = 0.029) and its third component score (HR 1.58, p = 0.017). CMR derived global strain measures are sensitive markers of clinical outcomes in patients with Fontan circulation, particularly in patients with the SRV morphology. Myocardial strain-time curve morphology specific to SLV and SRV patients inspired by unbiased PCA technique can further aid with predicting clinical outcomes.
心脏磁共振（CMR）通过心肌变形分析得出整体周向和纵向应变（GCS 和 GLS），这是一种越来越被广泛应用的方法，用于准确量化收缩功能并预测 Fontan 循环患者的临床事件。本研究的目的是使用主成分分析（PCA）来研究应变-时间曲线得出的心肌时间变形模式，以了解峰值以外的潜在应变特征。我们特别关注主导的单左心室（SLV）或单右心室（SRV）形态，进行了这项研究。
对接受随访 CMR 的 Fontan 手术后的患者进行标准容积和功能血流动力学分析，包括心肌变形参数（包括 GCS 和 GLS）。我们应用 PCA 以无偏倚的方式研究应变-时间曲线形态，并计算患者特定的形状评分。所有变量均进行单变量 Cox 回归分析，以检测包括死亡、心脏移植、蛋白丢失性肠病和塑料性支气管炎在内的复合临床结局。
共有 122 名患者（SLV=67，SRV=55），平均年龄为 12.7 岁，接受了全面的 CMR 分析。PCA 揭示了 3 种主要的应变曲线变化模式，无论单心室形态和所研究的应变类型如何。主成分（PC）描述了（1）应变-时间曲线幅度、（2）应变达峰时间和（3）应变-时间曲线的收缩后斜率的变化。
仅考虑 SLV 患者，GCS 是唯一预测临床事件的 CMR 变量（HR 1.46，p=0.020）。在 SRV 组中，临床事件的显著 CMR 预测因素是索引舒张末期（HR 1.02，p=0.023）和收缩末期（HR 1.03，p=0.022）容积、GCS（HR 1.91，p=0.003）及其相关的第一成分评分（HR 1.20，p=0.005）、GLS（HR 1.32，p=0.029）和其第三成分评分（HR 1.58，p=0.017）。
Fontan 循环患者的 CMR 衍生整体应变测量值是临床结局的敏感标志物，特别是在 SRV 形态的患者中。受无偏 PCA 技术启发的 SLV 和 SRV 患者的心肌应变-时间曲线形态可以进一步帮助预测临床结局。
