非瓣膜性房颤患者右心耳右心房超声特征与心肌细胞凋亡关系的研究

Relationship between ultrasonic characteristics of right atrial appendage and right atrium and apoptosis of atrial myocardium in patients with nonvalvular atrial fibrillation

目的研究非瓣膜性心房纤颤(NV-AF)右心耳(RAA)及右心房超声特征与心房肌细胞凋亡的关系。方法采用经食管超声观察25例NV-AF患者(观察组)和15例窦性心律者(对照组)的RAA及右心房变化,心肌细胞原位末端标记法(TUNEL法)检测RAA的心肌细胞凋亡指数。结果观察组RAA耳充血、排血峰速及速度积分、RAA及右心房射血分数均较对照组显著减小,RAA面积增大,心房肌细胞凋亡指数增高(P< 0．05)。RAA内自发性超声造影(SEC)现象检出率占16％,RAA及右心房内未发现血栓。对照组未检出SEC或血栓。相关分析显示,心房肌细胞凋亡指数与RAA充流、排血峰速、RAA及右房射血分数呈负相关(P均< 0．05),而与RAA及右心房面积呈正相关(P均<0．05),与右心室射血分数无相关性(P>0．05)。结论NV-AF患者的RAA及右心房改变与心房肌细胞凋亡密切相关,心肌细胞凋亡是其病理过程的中间或基础环节之一。

[Objective] To study the relationship between the ultrasonic characteristics of right atrial appendage （RAA） and right atrium（RA） and apoptosis of atrial myoeardium in patients with nonvalvular atrial fibrillation（NV-AF）. [Methods] Right atrial appendage and right atrium structure and function in 25 patients and 15 subjects with sinus rhythm were studied from transesophageal echocardiography. Cardiomyocyte apoptosis was identified by in situ TDT-mediated dUTP nick end labeling （TUNEL）. [Results] Compared with those in the control, the peak filling, emptying velocities and time-velocity integrals of RAA, the RAA ejection fraction and RA ejection fraction were singnificiently lower; the area of RAA was bigger and cardiomyocyte apoptosis index was higher（P〈0. 05）. And the spontaneous echo contrast （SEC） phenomenon was observed in 4 （16%） patients with NV-AF while SEC was not observed in any subjects in the control. The thrombi in RAA or RA were not detected in any subjects. Not any thrombi or SEC was found in the control group. Correlation analysis showed that cardiomyocyte apoptosis index had negative correlation with RAA peak filling, emptying velocities , RAA ejection fraction and RA ejection fraction （r =-0. 55,-0.49,-0. 45,-0. 36, P 〈 0. 05） . The cardiomyocyte apoptosis index didn＇t correlate with RV ejection fraction. [Conclusion] There is a close relationship between the changes of RAA and RA and apoptosis of atrial myocardium in patients with NV-AF. Apoptosis of atrial myocardium is one of the basic factors which influence development of fibrillation.