MRI在评估原发性扩张型心肌病患者心室功能中的应用

Application of MRI in Assessing Ventricular Function in Patients with Idiopathic Dilated Cardiomyopathy

目的研究核磁共振检查(MRI)评估原发性扩张型心肌病(IDCM)患者心室功能中的效果。方法回顾性分析85例IDCM患者资料,根据心功能分级标准分为Ⅰ-Ⅱ级(n=20)、Ⅲ级(n=35)和Ⅳ级(n=30),分析MRI与二维超声(2DE)评价心室功能价值。结果 85例IDCM患者均存在左右心室不同程度扩张,以左侧心室扩张为主,MRI检查中,36例左心扩大,左室多呈球形,室壁厚度变薄,49例双侧心室扩大,心肌运动弥漫性减弱;2DE检查所有患者均显示全心扩大,56例以左心室扩大为主,室间隔及左室后壁厚度变薄,室壁运动弥漫性减弱;随着IDCM患者心功能分级增高,MRI检查的LVEDV、LVESV逐渐升高,LVSV、LVEF、LVPER、LVPFP逐渐降低,不同等级差异显著(P<0.05);2DE检查的LVESV逐渐升高,LVEF逐渐降低,不同等级患者间差异显著(P<0.05);;2DE与MRI检查在室间隔、前壁、后壁厚度的测量上无显著性差异(P>0.05),在侧壁与心尖部厚度检查中差异显著(P<0.05)。结论 2DE与MRI均可有效评估IDCM患者心室功能,但2DE易低估左心室容积、重复性差,而MRI则可提供更多左心室功能、容积等参数,可重复性高,评估心脏功能和心室壁厚度更加准确,临床应用价值更高。

Objective To study the effects of magnetic resonance imaging（MRI） on ventricular function in patients with idiopathic dilated cardiomyopathy（IDCM）. MethodsThe data of 85 IDCM patients were retrospectively analyzed. According to the standard of cardiac function, they were divided into grade Ⅰ~Ⅱ（n=20）, grade Ⅲ（n=35） and grade Ⅳ（n=30）. The values of MRI and two-dimensional echocardiography（2 DE） in evaluation of ventricular function were analyzed. Results There were different degrees of left and right ventricle dilation among 85 IDCM patients, mainly in left ventricular dilation. In MRI examination, there were 36 cases of left ventricular enlargement with the mainly spherical left ventricle and the thinner wall thickness, and there were 49 cases of bilateral ventricular enlargement with the diffusely weakened myocardial motion. 2 DE examination showed that all patients were with complete heart enlargement, of which 56 cases were mainly left ventricular enlargement with thinner ventricular septum and left ventricular posterior wall thickness and diffusely weakened ventricular wall motion. With the increase of cardiac function grades in IDCM patients, the levels of LVEDV and LVESV by MRI were increased gradually while the levels of LVSV, LVEF, LVPER and LVPFP were gradually decreased, and there was significant difference among different grades（P〈0.05）. The LVESV level by 2 DE was increased gradually while the LVEF level was decreased gradually, and the differences among the different grades of patients were significant（P〈0.05）. There was no significant difference in the thickness of ventricular septum, anterior wall and posterior wall between 2 DE and MRI（P〉0.05）, but there were significant differences in the thickness of lateral wall and apex of heart（P〈0.05）. Conclusion Both 2 DE and MRI can effectively assess the ventricular function of IDCM patients, but 2 DE tends to underestimate left ventricular volume with poor reproducibility whereas MRI provides more parameters of left ventricular function and volume with high reproducibility. And MRI can more accurately assess the cardiac function and ventricular wall thickness, and it has high clinical application values.