CAJ | 학술논문

目的探讨具有防移位设计的可压缩性肺动脉支架瓣膜的防移位效果.方法将带瓣牛颈静脉缝在3个"Z"字型镍钛合金支架上,制作成喇叭口型肺动脉支架瓣膜.非体外循环下用推送器将其经右心室置入羊肺动脉瓣位置(n=6),分别于术后早期、术后2个月采用右心导管、心脏彩超、血流动力学测定、大体病理等方法评价置入瓣膜的位置和功能.结果 6只羊支架瓣膜均在正确位置释放.超声、右心导管造影以及血流动力学检查显示,术后早期、术后2个月置入瓣膜支架固定好,无移位,1例瓣膜收缩期跨瓣压差24 mm Hg,1例瓣膜轻度关闭不全,其他瓣膜功能良好.结论喇叭口型支架有助于防止瓣膜移位.
목적 탐토구유방이위설계적가압축성폐동맥지가판막적방이위효과.방법 장대판우경정맥봉재3개"Z"자형얼태합금지가상,제작성나팔구형폐동맥지가판막.비체외순배하용추송기장기경우심실치입양폐동맥판위치(n=6),분별우술후조기、술후2개월채용우심도관、심장채초、혈류동역학측정、대체병리등방법평개치입판막적위치화공능.결과 6지양지가판막균재정학위치석방.초성、우심도관조영이급혈류동역학검사현시,술후조기、술후2개월치입판막지가고정호,무이위,1례판막수축기과판압차24 mm Hg,1례판막경도관폐불전,기타판막공능량호.결론 나팔구형지가유조우방지판막이위.
Objective To evaluate the performance and antimigration effect of a bovine valve stent equipped with an anchoring mechanism implanted off-pump in pulmonary position over 2-month period,and to explore the antimigration effect of the new anchoring design.Methods A bell-shaped pulmonary valve stent(BPVS) was constructed by suturing a bovine jugular xenografts into 3 rings of "Z" nitinol stent.The ring in the distal extremity of valve stent bents outward (bell portion) to prevent the stent migration.The diameter of the bell portion is 20% larger than that of the proximal tubular part.Through a stent-graft delivery system (24 French) the BPVSs were implanted off-pump in pulmonary valve position on 6 sheep by trans-ventricular approach.Hemodynamic,epicardial echocardiography and angiography was performed early and 2-month late after the procedure for assessment of the position,sealing and function of the implanted valve.All grafts woe explainted 2 months after implantation and all explanted valve stents were inspected macroscopically,and the competence of me valve was tested in the in vitro pulsatile flow system.Results BPVSs were all successfully implanted off-pump in pulmonary position on 6 sheep,all 6 sheep survived the 2-month study time and no complications were noted.Angiographic,echocardiographic and macroscopic studies revealed good position of the valve stents with no stent migration as well as no erosion and fracture of the nitinol stents at the end of protocol.All BPVSs were echocardiographically and angiographiclly competent early after the procedure and no paravalvular leak was observed at 2-months follow-up period,four neovalves were competent,whereas one mild stenosis and one mild regurgitation were detected echocardiographically and angiographiclly at the end of the study;Hemodynamic evaluation revealed that one valve stent was mildly stenotic,with a 24mm pressure gradient across the valve stent,however no significant changes were found in pulmonary and right ventricular pressure as well as transvalvular pressure gradient before and immediately after the implantation and at the end of the protocol(P＜0.05).All six valves were free of calcification and thrombus formation,and the Ieaflets of four implanted valves were pliable and thin and perfectly mobile;whereas two of six were covered with fibrous tissue and post mortem examination revealed slight stiffening of leaflet with slightly narrowed orifice in one case,and with slightly incomplete coaptation in the other.Conclusion Transventricularly implantation of the bell-shaped nitinol valve stent was evaluated during a 2-month period in sheep in the present study showing a good structural and functional outcome with no migration.It indicates that the bell-shaped design is helpful in preventing the valve stent migration.