Sunthankar Sudeep, Parra David A, George-Durrett Kristen, Crum Kimberly, Chew Joshua D, Christensen Jason, Raucci Frank J, Xu Meng, Slaughter James C, Soslow Jonathan H
Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA.
Thomas P Graham Division of Pediatric Cardiology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA.
Cardiol Young. 2019 Dec;29(12):1459-1467. doi: 10.1017/S1047951119002397. Epub 2019 Nov 26.
Distinguishing between hypertrophic cardiomyopathy and other causes ofleft ventricular hypertrophy can be difficult in children. We hypothesised that cardiac MRI T1 mapping could improve diagnosis of paediatric hypertrophic cardiomyopathy and that measures of myocardial function would correlate with T1 times and extracellular volume fraction.
Thirty patients with hypertrophic cardiomyopathy completed MRI with tissue tagging, T1-mapping, and late gadolinium enhancement. Left ventricular circumferential strain was calculated from tagged images. T1, partition coefficient, and synthetic extracellular volume were measured at base, mid, apex, and thickest area of myocardial hypertrophy. MRI measures compared to cohort of 19 healthy children and young adults. Mann-Whitney U, Spearman's rho, and multivariable logistic regression were used for statistical analysis.
Hypertrophic cardiomyopathy patients had increased left ventricular ejection fraction and indexed mass. Hypertrophic cardiomyopathy patients had decreased global strain and increased native T1 (-14.3% interquartile range [-16.0, -12.1] versus -17.3% [-19.0, -15.7], p < 0.001 and 1015 ms [991, 1026] versus 990 ms [972, 1001], p = 0.019). Partition coefficient and synthetic extracellular volume were not increased in hypertrophic cardiomyopathy. Global native T1 correlated inversely with ejection fraction (ρ = -0.63, p = 0.002) and directly with global strain (ρ = 0.51, p = 0.019). A logistic regression model using ejection fraction and native T1 distinguished between hypertrophic cardiomyopathy and control with an area under the receiver operating characteristic curve of 0.91.
In this cohort of paediatric hypertrophic cardiomyopathy, strain was decreased and native T1 was increased compared with controls. Native T1 correlated with both ejection fraction and strain, and a model using native T1 and ejection fraction differentiated patients with and without hypertrophic cardiomyopathy.
在儿童中，区分肥厚型心肌病与其他导致左心室肥厚的病因可能存在困难。我们推测心脏磁共振成像（MRI）T1 映射可改善小儿肥厚型心肌病的诊断，并且心肌功能指标将与 T1 时间及细胞外容积分数相关。
30 例肥厚型心肌病患者完成了带有组织标记、T1 映射及钆延迟增强的 MRI 检查。从标记图像计算左心室圆周应变。在心肌肥厚的基底、中部、心尖及最厚区域测量 T1、分配系数及合成细胞外容积。将 MRI 测量结果与 19 名健康儿童及青年成人队列进行比较。采用 Mann-Whitney U 检验、Spearman 秩相关系数及多变量逻辑回归进行统计分析。
肥厚型心肌病患者左心室射血分数及指数质量增加。肥厚型心肌病患者整体应变降低，固有 T1 增加（四分位数间距[-16.0, -12.1]时为-14.3%，而[-19.0, -15.7]时为-17.3%，p<0.001；分别为 1015 毫秒[991, 1026]和 990 毫秒[972, 1001]，p = 0.019）。肥厚型心肌病患者的分配系数及合成细胞外容积未增加。整体固有 T1 与射血分数呈负相关（ρ = -0.63，p = 0.002），与整体应变呈正相关（ρ = 0.51，p = 0.019）。使用射血分数和固有 T1 的逻辑回归模型区分肥厚型心肌病与对照组的受试者工作特征曲线下面积为 0.91。
在该小儿肥厚型心肌病队列中，与对照组相比，应变降低，固有 T1 增加。固有 T1 与射血分数及应变均相关，并且使用固有 T1 和射血分数的模型可区分有无肥厚型心肌病的患者。
