MRI延迟强化在肥厚型心肌病中的临床意义

Late gadolinium enhancement MRI in patients with hypertrophic cardiomyopathy

目的回顾性分析肥厚型心肌病（HCM）左心室心肌肥厚MRI延迟强化与临床特征的关系。方法收集79例HCM患者行MR检查，先常规实施心脏结构和功能检查，再进行钆对比剂延迟强化（LGE）扫描。按17节段法，分别测量心肌厚度、射血分数、左心室舒张期末容积等，并进行LGE评分。性别、胸闷等组间LGE的差异采用卡方检验，临床特征与测得数据采用Logistic回归分析，并以分析出阳性症状为参考标准评价LGE预测心脏事件的准确性，比较ROC曲线下面积。结果79例患者共计1343节段，其中肥厚节段633个，基底段前室间隔（第2节段）肥厚节段数最多（64个），其次为第9、3和8节段，分别为58、57和57个。LGE显示受累节段433个，第2节段最多（51个），其次为第8、9和14节段，分别为39、37和36个。左心房前后直径、LGE是心房颤动的独立预测因子（HR分别为1．11和1．12，P≤0．01），ROC曲线下面积分别为0．726、0．743；LGE是非持续性室性心律失常（NSVT）的独立预测因子（HR=1．15，P≤0．01），ROC曲线下面积为0．817。结论HCM患者心肌肥厚及LGE呈不对称性分布，LGE是HCM发生NSVT及心房颤动的独立危险因素。

Objective To retrospectively analyze the correlation of late gadolinium enhancement （LGE） on MRI with the extent of hypertrophic left ventricular myocardium and clinical features in hypertrophic eardiomyopathy. Methods Seventy-nine patients with hypertrophic cardiomyopathy were included in this study. Routine and functional cardiac MRI scans were performed, and then all patients underwent late gadolinium enhancement （ LGE ） MRI. The thickness of myocardium, ventricular function including ejection fraction （EF） and left ventricular end diastolic volume （LVEDV） according to the traditional 17-sectional method were measured and the LGE score was calculated. The Chi-square test and Logistic regression analysis were used to assess the accuracy of LGE predicting cardiac events and the area under ROC curve was compared. Results A total of 1343 segments including 633 hypertrophic segments in 79 patients were enrolled for the analysis. The basal anlerior ventricular septum was the most commonly involved hypertrophic segment （ n = 64 ） , following by the 9,3,8 segments （ n = 58,57,57, respectively）. LGE was shown in 433 segments, while the basal anterior ventricular septurn was the most commonly involved segment （ n = 51 ）, following by the 8,9,14 segments （ n = 39,37,36, respectively）. The （a-p） diameter of the left atrium and LGE were the independent predictors of atrial fibrillation （ HR = 1.14,1.20, respectively, P≤0. 01 ） , and the area under ROC （AUC） was 0. 726 and 0. 743, respectively. LGE extent of the leftventricle was the independent predictor of NSVT （HR = 1.15, P ≤ 0.01 ）, and the AUC was 0. 817. Conclusion The hypertrophic segments and LGE were asymmetric distributed, and the extent of LGE is an independent risk factor for the NSVT and atrial fibrillation.