心肌致密化不全的MRI与超声心动图对比研究

Comparative study between MRI and echocardiography in noncompaction of ventricular myocardium

目的探讨心肌致密化不全(NVM)的 MRI 和超声心动图征象,评价 MRI 对诊断心肌致密化不全的价值。方法对常规超声心动图多切面诊断为 NVM 的14例患者进行 MR 检查。MR扫描序列包括黑血技术:双反转恢复快速自旋回波(DIRFSE)和三反转恢复快速自旋回波(TIRFSE)序列;亮血技术:快速稳态进动采集(FIESTA)序列。所有患者进行短轴面、四腔面和长轴面检查。结果 14例患者 MRI 和超声心动图显示13例左室受累,1例双室受累,以心尖部和中间部多见。MRI 共显示54段,超声心动图显示53段,对各段的显示能力两者差异无统计学意义(P=1.000)。受累心肌分层,非致密化心肌和致密化心肌厚度比值(N/C)测量 MRI 与超声心动图分别为3.37±0.89、3.19±0.82。非致密化心肌层信号不均匀,可见异常粗大的肌小梁和其间深陷的隐窝,隐窝内血流与心腔内相通。合并室壁瘤形成1例,冠状动脉造影显示正常。1例因进行性心力衰竭而行心脏移植,受累心脏病理解剖显示心腔内异常粗大、增多的肌小梁和深陷的隐窝,与 MRI 有较好的一致性。结论 NVM 的 MRI 表现具有一定特征,多序列、多平面的 MRI 对于诊断 NVM 有重要的临床价值。与超声相比,MRI 具有较高的软组织分辨率和空间分辨率,对于心肌分层的显示优于超声。

Objective To investigate the MRI and echocardiography manifestations of noncompaction of ventricular myocardium（NVM） and assess the role of MRI in the diagnosis of NVM by comparing it with echocardiography. Methods Fourteen cases of NVM diagnosed by echocardiography were examined with MRI, including scanning of black-blood sequences, double inversion recovery fast spin echo （DIRFSE） and triple inversion recovery fast spin echo （ TIRFSE）, and white blood sequence： fast imaging employ steady state acquisition（FIESTA）. Scanning plane includes short axis view, four-chamber view and long axis view. Results Both MRI and echocardiography displayed involvement of left ventricles in thirteen cases and involvement of double ventricles in one case. Apexes of heart and the intermedius are commonly affected. MRI showed 54 segments and echocardiography showed 53 segments affected, and there is no significant difference between the capability of MRI and echocardiography （ P = 1. 000 ）. The affected myocardium consisted of two layers： subendocardial noncompacted myocardium and epicardial compacted myocardium, and the ratio measurement of N/C by MRI was 3.37 ± 0. 89 and it was 3. 19 ± 0. 82 by echocardiography. Noncompacted myocardium was characterized by prominent and excessive myocardial trabeculations and deep intratrabecular recesses, in which the blood flow was communicated with the ventricle. One case was complicated with ventricular aneurysm, and coronary arteriography was performed with unremarkable findings. One case underwent heart transplantation because of progressive heart failure, Gross findings demonstrated prominent muscular trabeculations with deep intratrabecular recesses, which coincided well with MRI findings. Conclusion The MRI manifestation of NVM is characteristic, and MRI with multiple series and planes is helpful in the diagnose of NVM. Compared with echocardiography, MRI could display the pathological cardiac muscle more clearly, because of its high soft-tissue resolution and spatial resolution.