左心室致密化不全且左心室射血分数正常患者中，通过心脏磁共振特征追踪评估的左心室分形维数与应变受损之间的相关性。

Correlation between left ventricular fractal dimension and impaired strain assessed by cardiac MRI feature tracking in patients with left ventricular noncompaction and normal left ventricular ejection fraction.

作者信息

Yu Shiqin, Chen Xiuyu, Yang Kai, Wang Jiaxin, Zhao Kankan, Dong Wenhao, Yan Weipeng, Su Guohai, Zhao Shihua

机构信息

MR Center, Fuwai Hospital, Stata Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases of China, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 167, Beilishi Road, Xicheng District, Beijing, 100037, China.

Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, SZ University Town, Shenzhen, 518055, China.

出版信息

Eur Radiol. 2022 Apr;32(4):2594-2603. doi: 10.1007/s00330-021-08346-2. Epub 2021 Nov 15.

DOI:10.1007/s00330-021-08346-2

PMID:34779872

Abstract

OBJECTIVES

To investigate the correlation between the extent of excessive trabeculation assessed by fractal dimension (FD) and myocardial contractility assessed by cardiac MRI feature tracking in patients with left ventricular noncompaction (LVNC) and normal left ventricular ejection fraction (LVEF).

METHODS

Forty-one LVNC patients with normal LVEF (≥ 50%) and 41 healthy controls were retrospectively included. All patients fulfilled three available diagnostic criteria on MRI. Cardiac MRI feature tracking was performed on cine images to determine left ventricular (LV) peak strains in three directions: global radial strain (GRS), global circumferential strain (GCS), and global longitudinal strain (GLS). The complexity of excessive trabeculation was quantified by fractal analysis on short-axis cine stacks.

RESULTS

Compared with controls, patients with LVNC had impaired GRS, GCS, and GLS (all p < 0.05). The global, maximal, and regional FD values of the LVNC population were all significantly higher than those of the controls (all p < 0.05). Global FD was positively correlated with the end-diastolic volume index, end-systolic volume index, and stroke volume index (r = 0.483, 0.505, and 0.335, respectively, all p < 0.05), but negatively correlated with GRS and GCS (r = - 0.458 and 0.508, respectively, both p < 0.001). Moreover, apical FD was also weakly associated with LVEF and GLS (r = - 0.249 and 0.252, respectively, both p < 0.05).

CONCLUSION

In patients with LVNC, LV systolic dysfunction was detected early by cardiac MRI feature tracking despite the presence of normal LVEF and was associated with excessive trabecular complexity assessed by FD.

KEY POINTS

• Left ventricular global strain was already impaired in patients with extremely prominent excessive trabeculation but normal left ventricular ejection fraction. • An increased fractal dimension was associated with impaired deformation in left ventricular noncompaction.

摘要

目的

探讨在左心室心肌致密化不全（LVNC）且左心室射血分数（LVEF）正常的患者中，通过分形维数（FD）评估的过度小梁化程度与通过心脏磁共振成像（MRI）特征追踪评估的心肌收缩力之间的相关性。

方法

回顾性纳入41例LVEF正常（≥50%）的LVNC患者和41名健康对照者。所有患者均符合MRI上的三项可用诊断标准。在电影图像上进行心脏MRI特征追踪，以确定左心室（LV）在三个方向上的峰值应变：整体径向应变（GRS）、整体圆周应变（GCS）和整体纵向应变（GLS）。通过对短轴电影图像堆栈进行分形分析来量化过度小梁化的复杂性。

结果

与对照组相比，LVNC患者的GRS、GCS和GLS均受损（所有p<0.05）。LVNC患者群体的整体、最大和区域FD值均显著高于对照组（所有p<0.05）。整体FD与舒张末期容积指数、收缩末期容积指数和每搏输出量指数呈正相关（r分别为0.483、0.505和0.335，所有p<0.05），但与GRS和GCS呈负相关（r分别为-0.458和0.508，两者p<0.001）。此外，心尖FD也与LVEF和GLS弱相关（r分别为-0.249和0.252，两者p<0.05）。