肥厚性心肌病心传导系统病理学观察

Pathologicalchangesofcardiacconductingsystemincasesofhypertrophiccardiomyopathy

为研究肥厚性心肌病心传导系统的病理改变，作者对１０例肥厚性心肌病心传导系统采用纵切法，常规染色切片，光镜下观察，结果发现心传导系统有两种形态学改变：（１）与肥厚性心肌病的心肌相似的变化，即细胞肥大、走向紊乱伴纤维化。（２）房室束分叉部甚至连同左束支起始段牵长变扁、细胞变细、脂肪浸润。以上改变表明，肥厚性心肌病心传导系统变化既有先天性发育异常，也可由于房室束随室间隔肥厚压迫而相应地牵长、变细。肥厚性心肌病患者发生猝死，除因流出道狭窄、冠状动脉灌注不足、左心顺应性降低外，尚需考虑心传导系统病变，导致传导功能障碍，引起严重心律失常。

Thecardiacconductingsystem(CCS)of10casessufferedfromhypertrophiccar-diomyopathyweresampledaccordingtothemodifiedmethoddesignedbytheauthors.TwentytothirtytissuesectionsfromdiferentpartsoftheCCSfromeachcaseweretaken.AlsectionswerestainedbyH&Eandobservedundermicroscope.TwotypesofpathologicalchangesoftheCCSwereobserved.Onewaschangescorrespondingtogeneralchangesinotherpartsoftheheart,suchashy-pertrophyofthemyofibers,disorientationofthecelsandinterstitialfibrosis.TheotherwaschangeswithstretchingandflatteningofthecelsinvolvingthebifurcationoftheAVbundleoreventhecom-mencingportionoftheleftbundlebranch,andfatyinfiltrationoftheseparts.Thesechangesindi-catethatthechangesofCCSincasesofhypertrophiccardiomyopathymaybeduenotonlytoantena-talanomalyoftheheart,butalsotopostnatalhypertrophyoftheinterventricularseptumwithstretchingandflateningofthestructure.Thecauseofsuddenunexpecteddeathsinthesecasescouldbeatributedeithertothenarrowingofoutflowtract,insuficientcoronaryperfusionandloweredcomplianceoftheleftheartasoftendescribed,ortothechangesintheCCSasdescribedinthispa-per,whichleadstoabnormalcardiacconductionandhencetoseverearrhythmia.