Zheng Y C, Lu M J, Chen X Y, Yang K, Yin G, Wang K, Zhao S H
Department of Magnetic Resonance Imaging, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100037, China.
Department of Image Diagnoses, Shanxi Dayi Hospital, Shanxi Academy of Medical Sciences, Taiyuan 030032, China Zheng Yucong's personal profile is in Shanxi Dayi Hospital, Shanxi Academy of Medical Sciences, Taiyuan 030032, China.
Zhonghua Xin Xue Guan Bing Za Zhi. 2019 Aug 24;47(8):622-627. doi: 10.3760/cma.j.issn.0253-3758.2019.08.006.
To investigate the cardiovascular magnetic resonance (CMR) imaging characteristics and influence factors of aortic insufficiency (AI) patients with myocardial fibrosis. This retrospective study included 59 AI patients who received CMR and transthoracic echocardiography (TTE) examinations from June 2011 to February 2015. AI patients were divided into 2 groups: bicuspid aortic valve (BAV) group (30) and non-BAV group (29). Patients were also divided into late gadolinium enhancement (LGE) group (27) and non-LGE group (32). The baseline clinical characteristics were collected through electronic medical records. Hemodynamic parameters such as grade of AI, cardiac functional parameters and LGE mass fraction (LGE%) were measured by CMR post-processing analysis. Kappa test was used to assess the consistency of AI severity between CMR and TTE, and the multivariate logistic regression analysis was performed to evaluate influence factors of myocardial fibrosis in AI patients. (1) 56 (94.9%) patients were male, and the mean age was (44.2±11.0) years old. There was no significant difference in age and gender, hypertension, hyperlipidemia, alcoholic consumption between BAV and non-BAV group (all 0.05). There were a higher proportion of smoking history (0.008), a lower body mass index (BMI) (0.020) in the LGE group than in the non-LGE group. (2) The accuracy of CMR in diagnosis of BAV was 96.7% (29/30) compared to the gold standard. In the BAV group, 20 patients (66.7%) were with fusion of left and right cusp (L-R), 5 patients (16.7%) were with fusion of right and noncoronary cusp (R-N), 5 patients (16.7%) were with fusion of left and noncoronary cusp (L-N); patients with BAV had larger left ventricular end diastolic volume index (LVEDVi), left ventricular end systolic volume index (LVESVi), higher proportion of LGE and lower left ventricular ejection fraction (LVEF) than those in non-BAV group (all 0.05). There were 19 patients with BAV in the LGE group, the cases of L-R, R-N, L-N were 10 (52.6%), 5 (26.3%), and 4 (21.1%), respectively. In the non-LGE group, patients with BAV of L-R, R-N, L-N were 10 (90.9%), 0, and 1 (9.1%), respectively. Patients with LGE had lower body surface area (BSA), LVEF and larger LVEDVi, LVESVi, left ventricular mass index (LVMi) and higher proportion of BAV compared patients without LGE. In addition, the proportion of moderate and severe AI patients was significantly higher in BAV group than in non-BAV group (0.009). (3) The consistency of CMR and TTE in evaluating the severity of AI patients: the agreement between TTE and CMR regarding AI severity was satisfactory (kappa value was 0.624, 95 0.402-0.831, <0.001). (4) The linear regression analysis demonstrated a negative correlation between LVEF and LGE% in BAV and non-BAV group (0.001). The multivariate logistic regression analysis showed that the presence of BAV was an independent risk factor of left ventricucar fibrosis (5.050, 95 1.220-20.908, 0.025) after adjustment for LVEF, hypertension, LVEDVi and LVMi. Multi-parametric CMR provides a satisfactory noninvasive tool for estimation of myocardial fibrosis and ventricular remodeling in patients with AI, and BAV is an independent risk factor for myocardial fibrosis in patients with AI.
探讨主动脉瓣关闭不全(AI)合并心肌纤维化患者的心血管磁共振(CMR)成像特征及影响因素。本回顾性研究纳入了2011年6月至2015年2月期间接受CMR和经胸超声心动图(TTE)检查的59例AI患者。AI患者分为两组:二叶式主动脉瓣(BAV)组(30例)和非BAV组(29例)。患者还分为延迟钆增强(LGE)组(27例)和非LGE组(32例)。通过电子病历收集基线临床特征。通过CMR后处理分析测量血流动力学参数,如AI分级、心功能参数和LGE质量分数(LGE%)。采用Kappa检验评估CMR与TTE之间AI严重程度的一致性,并进行多因素逻辑回归分析以评估AI患者心肌纤维化的影响因素。(1)56例(94.9%)患者为男性,平均年龄为(44.2±11.0)岁。BAV组和非BAV组在年龄、性别、高血压、高脂血症、饮酒方面无显著差异(均P>0.05)。LGE组吸烟史比例较高(P=0.008),体重指数(BMI)较低(P=0.020)。(2)与金标准相比,CMR诊断BAV的准确率为96.7%(29/30)。在BAV组中,20例(66.7%)为左右瓣叶融合(L-R),5例(16.7%)为右瓣叶与无冠瓣叶融合(R-N),5例(16.7%)为左瓣叶与无冠瓣叶融合(L-N);BAV患者的左心室舒张末期容积指数(LVEDVi)、左心室收缩末期容积指数(LVESVi)较大,LGE比例较高,左心室射血分数(LVEF)较低,与非BAV组相比差异均有统计学意义(均P<0.05)。LGE组中有19例BAV患者,L-R、R-N、L-N的病例分别为10例(52.6%)、5例(26.3%)和4例(21.1%)。在非LGE组中,L-R、R-N、L-N的BAV患者分别为10例(90.9%)、0例和1例(9.1%)。与无LGE的患者相比,有LGE的患者体表面积(BSA)、LVEF较低,LVEDVi、LVESVi、左心室质量指数(LVMi)较大,BAV比例较高。此外,BAV组中重度AI患者的比例显著高于非BAV组(P=0.009)。(3)CMR与TTE评估AI患者严重程度的一致性:TTE与CMR在AI严重程度方面的一致性良好(kappa值为0.624,95%CI为0.402-0.831,P<0.001)。(4)线性回归分析显示,BAV组和非BAV组中LVEF与LGE%呈负相关(P<0.001)。多因素逻辑回归分析显示,在调整LVEF、高血压、LVEDVi和LVMi后,BAV的存在是左心室纤维化的独立危险因素(OR=5.050,95%CI为1.220-20.908,P=0.025)。多参数CMR为评估AI患者的心肌纤维化和心室重构提供了一种令人满意的非侵入性工具,BAV是AI患者心肌纤维化的独立危险因素。