延迟增强MRI对心房颤动患者左心房心肌纤维化的评估价值

The assessment of the left atrial myocardial fibrosis of atrial fibrillation with late Gadolinium enhancement MRI

目的 探讨2D延迟增强MRI（LGE-MRI）技术对心房颤动（简称房颤）患者左心房心肌纤维化评估的临床应用价值。方法 回顾性分析我院自2015年3月至2016年12月拟行射频消融术的房颤患者49例，所有患者术前均行LGE-MRI检查。由2名富有经验的影像诊断医师对MR图像分析评估，轴位像上将左心房划分为8个象限，根据延迟强化程度及范围，将左心房纤维化分为4级。全部患者三维电解剖标测（CARTO）,左心房电解剖图像均在房颤导管消融术前复律后窦性心律下左房基质标测取得，并根据其低电压分布分级。采用Kappa检验来评估MRI延迟增强左心房心肌纤维化和CARTO系统左心房心内膜电压重建图像分级的一致性。结果 49例心房颤动患者LGE-MRI及CARTO左心房电解剖图像均成功完成。LGE-MRI左心房纤维化分级0级17例，Ⅰ级10例，Ⅱ级11例，Ⅲ级11例；CARTO心房纤维化分级0级17例，Ⅰ级9例，Ⅱ级12例，Ⅲ级11例。LGE-MRI心房纤维化诊断准确率为81.6%（40/49），与CARTO分级间一致性检验好（Kappa=0.751，P〈0.01）。结论 LGE-MRI技术能够较准确评估房颤患者左心房心肌纤维化程度，有助于临床对合适的患者行导管消融术。

Objective To investigate the clinical value of 2 dimension late Gadolinium enhancement MRI （LGE-MRI） technique for the evaluation of atrial myocardial fibrosis in patients with atrial fibrillation.Methods Forty-nine cases of atrial fibrillation in our hospital from March 2015 to December 2016 were retrospectively collected. The LGE-MR was acquired by the Siemens 3.0 T MR machine before the catheter ablation. The findings of LGE-MR were evaluated by two experienced doctors. The left atrium （LA） were manually segmented into 8 regions in axial view. All patients were classified into 4 stages based on the extent of enhancement, stage 0： absence of enhancement, stage Ⅰ： enhancement appeared in minimal two consecutive slices in single region, stage Ⅱ： enhancement in two regions, stage Ⅲ： enhancement in three or more regions. All electroanatomic maps were obtained after electrical conversion during catheter ablation. The Kappa test was used to assess the consistency of LGE-MRI left atrial myocardial fibrosis and CARTO system of the left atrial endocardial voltage reconstruction.Results Forty-nine cases of atrial fibrillation with LGE-MRI and CARTO were included. There were 17 cases of atrial fibrosis stage 0, 10 cases of stage Ⅰ, 11 cases of stage Ⅱ, 11 cases of stage Ⅲ according to LGE-MRI findings;There were 17 cases of atrial fibrosis stage 0, 19 cases of stage Ⅰ, 12 cases of stage Ⅱ, 11 cases of stage Ⅲ with reference to CARTO findings. The diagnostic accuracy of the LGE-MRI atrial fibrosis was 81.6% （40/49）, of which the correlation was good （Kappa= 0.751, P〈0.001）.Conclusions LGE-MRI can accurately assess the degree of left atrial myocardial fibrosis in patients with atrial fibrillation, help to select the proper candidate and strategy in catheter ablation.