经静脉置入起搏/除颤导线引起的心脏血管慢性病理改变

Chronic transvenous pacemaker/implantable cardioverter defibrillator leads implantation induced pathological changes

目的 观察长期置入起搏/除颤导线相关的慢性病理学改变.方法 本研究共包括3部分,第一对2008年3月至2011年3月38例应用准分子激光消融拔除的患者的83根起搏/除颤导线的病理学观察,第二对1例应用准分子激光消融拔除起搏/除颤导线死亡患者的尸体进行解剖研究,第三对10例既往置入起搏/除颤导线后因各种原因死亡患者的尸体进行解剖研究.结果 导线在血管内和心腔内可以形成广泛的纤维结缔组织包裹和粘连.上腔静脉近右心房处常粘连较为严重,且此处较薄弱,外侧为胸膜腔,易穿孔且穿孔后局部不能产生压迫止血作用,是本研究中1例拔出导线致死的原因.导线与三尖瓣和腱索的粘连往往较严重.位于心尖部右心室游离壁的导线尖端离心外膜较近.导线及血管、心腔内壁的血栓较常见,甚至有较大的血栓（尤其心耳内）.结论 经静脉置入的起搏/除颤导线在血管内和心腔内可形成广泛的纤维结缔组织包裹和粘连,导线和三尖瓣及腱索形成复杂的解剖关系和严重的粘连,有些心室导线的顶端已经进入肌层、接近心外膜,导线及血管、心腔内壁的血栓较常见.上腔静脉近心房处组织薄弱且粘连严重,导线拔出操作可导致透壁性损伤而致患者死亡.

Objective Widely pacemaker/implantable cardioverter defibrillator （ICD） implantation is also related to an increasing need for transvenous lead extraction.Understanding the location and extent of pathological changes,including adhesions and fibrous tissue formation along the course of chronic pacemaker/ICD leads,are essential for operators performing lead extraction operations in order to reduce the potential life threatening complications.Methods Three parts are included in the research,pathological examination on 83 extracted pacemaker/ICD leads using excimer laser technique from March 2008 to March 2011,autopsy examination of one died patient during lead extraction for lead-related infective endocarditis,and anatomical analysis on pacemaker/ICD leads from 10 patients died of other non-cardiac causes.Results Extensive encapsulated fibrous tissue around the leads and extensive adhesion/fibrosis along the course of the leads from venous entry site to the lead/myocardial interface could be detected on transvenous pacemaker/ICD leads.Since the tissue at the junction between superior vena cava （SVC） and right atrium （RA） is very thin,free of pericardium,thus,this is a common place for extensive adhesion/fibrosis and myocardial perforation/tear during lead extraction,which accounted for one death during extraction in our cohort.Extensive adhesion and fibrosis were also observed at the tricuspid valve and subvalvular structures.Leads implanted to the right ventricular apex were close to the epicardial surface and prone to perforation through myocardium.It is common to observe thrombus on the leads or at the interface between leads and myocardial tissue,especially at right atrial appendage （RAA） at the site of lead insertion.Conclusion Extensive adhesions and fibrosis can be commonly seen along the course of pacemaker/ICD leads,and at SVC to RA junction,the tricuspid valve/subvalvular structures,and RA/RV lead interface.The tissue at SVC to RA junction is very thin,making it vulnerable for myocardial perforation/tear during lead extraction.Thrombus is commonly seen along the leads or at the lead-tissue interface.