缓慢心律失常患者心内膜心肌活检的临床病理及超微结构研究

Pathological and ultrastructural study of myocardium in patients with bradyarrhythmias

目的 通过对植入起搏器的缓慢心律失常患者右心室心肌的临床病理研究及超微结构分析 ,探讨缓慢心律失常病因、判断病理改变程度及超微结构特点。 方法 对 13例需植入起搏器的缓慢心律失常患者在植入术中行心内膜心肌活检。三度房室阻滞 5例 ,病态窦房结综合征 8例。标本分别进行光镜及电镜检查。以 5例高血压病 期患者为对照。采用 Sekiguchi M的组织病理学半定量分析方法 ,按照病变严重程度进行 4级病理计分。 结果 病理诊断 :心肌病 1例、非特异性改变 12例。光镜结果 :缓慢心律失常患者均有不同程度心肌细胞肥大、心肌变性及间质纤维化 ,比较病态窦房结综合征组和三度房室阻滞组患者改变差异无显著性 (P>0 .0 5 )。组织病理学衰竭指数平均值 (2 .2± 1.2 )。电镜结果 :病态窦房结综合征组和三度房室阻滞组比较 ,病态窦房结综合征组线粒体数目增加、肌浆网扩张、脂褐质沉着增加及空泡变性差异均有显著性 (P<0 .0 5 )。与对照组比较 :缓慢心律失常患者线粒体数目增加、线粒体形态改变、空泡变性及肌原纤维断裂疏松化差异均有显著性 (P<0 .0 5 )。 结论 心内膜心肌活检对于了解缓慢心律失常发病原因缺乏特异性 ,对判断病理改变程度及超微结构有一定价值。缓慢心律失常者心肌均有不同程度病理改?

Objective The aim of this study is to investigate the etiology of bradyarrhythmias and reveal the relationship between bradyarrhythmias and pathological changes as well as ultrastructural features of ventricular myocardium.Methods Right ventricle endomyocardial biopsies(EMB) were performed in 13 patients diagnosed of bradyarrhythmias during the pacemaker implantation procedule,including 5 cases with third degree atrioventricular block(AVB) and 8 cases with sinus node dysfunction (SND).The specimens were examined with the optical microscope and electronic microscope respectively.Control group consisted of 5 patients with stage one essential hypertension.Semiquantitative assessment was used to evaluate the pathological changes in each patient,0,1,2,3 were scored respectively according to the severity of pathological changes (-,+,++,+++).Results Among the 13 cases with bradyarrhythmias,12 had non specific pathologic changes,and only one patient had cardiomyopathy.Cellular hypertrophy,myocardial degeneration and interstitial fibrosis were found in all 13 cases under optical microscope.There were no statistical significance( P >0.05) when comparing the pathological changes in patients with SND and AVB.Average histopathological contractility failure index(HCFI) was (2.2±1.2).Under electronic microscope,there is significant increase in the numbers of mitochondrions as well as change of morphology,dense bodies,and myofibril disruption( P <0.05) in SND group.Conclusion Right ventricle endomyocardial biopsy is lack of specificity in defining the etiology of bradyarrhythmias,though it is valuable in a certain extent to verdict the pathological and ultrastuctural changes in these patients.There were diverse pathological changes in myocardium of patients with bradyarrhythmias,slightly under optical microscope and more obviously under electronic microscope.