肥厚型心肌病伴左心室心尖部室壁瘤的MRI延迟强化特征分析

MRI late gadolinium enhancement of left ventricular apical aneurysms in hypertrophic cardiomyopathy

目的 探讨肥厚型心肌病（HCM）伴左心室心尖部室壁瘤（LVAA）的MR对比延迟强化（LGE）特征及其预后意义.方法 本研究为回顾性.2004年8月至2013年8月,搜集HCM合并LVAA患者30例.所有患者均除外冠心病并接受心脏MR（CMR）延迟强化检查,5例患者获得病理结果 证实.测量患者房室大小、室壁瘤大小、左心室射血分数,分析瘤壁延迟强化情况并进行随访.采用独立样本t检验比较LGE阳性和阴性患者的各测量指标,COX回归分析不良心血管事件的相关因素.结果 30例患者中,瘤壁LGE阳性21例、阴性9例.LGE阳性和阴性患者室壁瘤大小分别为（16.4±11.5）和（20.3±9.8）mm,差异无统计学意义（P=0.63）.其中,1例患者随访中观察到LVAA从非延迟强化向延迟强化的转变过程.病理学结果 表明,LGE阳性的LVAA对应心肌纤维瘢痕组织,而LGE阴性的LVAA对应存活心肌组织.随访结果 证实,LVAA的延迟强化和瘤体大小与患者预后有相关趋势（LVAA延迟强化,HR=7.94,P=0.064;LVAA瘤体大小,HR=1.08,P=0.009）.结论 HCM伴LVAA患者中,MR LGE技术具有重要的临床意义,LGE能够判断室壁瘤纤维瘢痕并具有预后价值.

Objectives To discuss the characteristics of late gadolinium enhancement （LGE） magnetic resonance （MR） imaging in patients with hypertrophic cardiomyopathy （HCM） and left ventricular apical aneurysm （LVAA） and its related prognostic value. Methods Thirty HCM patients with LVAA were collected from August 2004 to August 2013. All cases with coronary artery diseases were ruled out, and all patients underwent LGE derived by cardiac MR （CMR）. Five cases of LVAA were pathological confirmed. Atrial and ventricular diameters, apical aneurysm diameters and left ventricular ejection fraction were measured, and apical aneurysm LGE was evaluated. All patients were then followed up. Comparisons in continuous parameters between patients with or without LGE were performed by independent t test. A Cox proportional hazard model was used to estimate the hazard rate for adverse cardiovascular events. Results LGE was identified in 21 LVAAs and non-LGE in 9 LVAAs. Between two groups, there was no significant difference in the size of LVAA [（16.4± 11.5） mm vs. （20.3 ± 9.8） mm, P=0.63]. In particular, the complete transition from non-LGE to LGE LVAA was recorded during follow-up in one patient. Pathological findings confirmed that LGE indicated fibrous tissue in LVAA, and LVAA without LGE indicated viable myocardium. The follow-up suggested that the patterns and the size of LVAA were associated with the adverse events in these patients （LGE of LVAA, HR=7.94, P=0.064; the size of LVAA, HR=1.08, P=0.009）. Conclusions LGE-MR had important clinical significance in HCM patients with LVAA. LGE in LVAA corresponded with the fibrous tissue and was associated with the prognosis.