手工缝制的膨体聚四氟乙烯带瓣管道在右室流出道重建中的应用

Hand-sewn expanded polytetrafluoroethylene valved conduit for right ventricular outflow tract reconstruction

目的:由于缺乏大口径肺动脉带瓣管道产品,手工缝制的膨体聚四氟乙烯(expanded polytetrafluoroethylene,ePTFE)带瓣管道逐渐被国际上众多心脏中心用于右室流出道(right ventricular outflow tract,RVOT)重建。本研究旨在总结e PTFE带瓣管道植入后的早期临床结果,并结合国内外最新进展总结管道的缝制技术,为其推广应用提供参考。方法:纳入2018年10月至2020年10月于中南大学湘雅二医院使用ePTFE带瓣管道进行RVOT重建的21例患者,手术时年龄4.3~43.8(中位数15.1)岁,体重(38.9±4.1)kg。14例为再次行RVOT重建,其中12例为法洛四联症(tetralogy of Fallot,TOF)术后6.3~31.0(中位数13.8)年肺动脉瓣反流患者,2例为牛颈静脉带瓣管道(bovine jugular vein conduit,BJVC)衰败;7例为Ross手术,其中3例以主动脉瓣狭窄为主,2例以主动脉瓣反流为主,2例同时存在中度及以上的狭窄和反流。ePTFE带瓣管道均在术中按统一标准缝制,3叶瓣膜等大,瓣窦底缘呈圆弧形;瓣叶游离缘呈直线形,长度比管道直径约长1 mm;瓣窦高度为管道直径的4/5;瓣叶交界高度为瓣窦高度的3/4;裁剪后连续不穿透缝合至Gore-Tex血管内面以制成带瓣管道。直径18、20、22 mm的带瓣管道各使用2例、9例、10例。总结手术结果、术后康复速度和并发症,分析术后心功能状态和管道血流动力学状态变化趋势。结果:在ePTFE带瓣管道重建RVOT术中,2例Ross手术患者同期行二尖瓣机械瓣置换,2例TOF术后肺动脉反流患者同期行左右肺动脉加宽成形,1例BJVC衰败患者同期行三尖瓣成形。再次RVOT重建手术转流时间为(130.9±16.9)min,仅1例阻断主动脉行室间隔残余漏修补;Ross手术转流时间为(242.7±20.6)min,阻断时间为(145.6±10.5)min。术后呼吸机辅助、监护室停留和住院时间分别为3.5 h~7.7 d(中位数17.1 h)、11.2 h~29.5 d(中位数1.9 d)和6.0~56.0(中位数13.0)d。患者均存活出院,出院后随访率100%,中位随访时间15.0(13.0~39.0)个月。随访期无死亡;1例患者在行Ross术后2个月因右冠状动脉狭窄行支架植入,1例患者再次RVOT重建术后1年因右肺动脉开口狭窄行球囊扩张;术后6个月所有患者心功能恢复为NYHA I级;出院前经胸超声心动图测量管道跨瓣峰值压差为(9.4±2.6)mmHg(1 mmHg=0.133 kPa),末次随访的跨瓣峰值压差为(18.3±6.1)mmHg,随访期间管道压差无明显增加(P=0.134),管道瓣膜均无轻度及以上的反流。结论:手工缝制的ePTFE带瓣管道用于RVOT重建切实可行,可有效填补临床中大口径肺动脉带瓣管道的空缺,是一种非常具有临床应用前景的RVOT重建材料。笔者设计的ePTFE带瓣管道的制作简单、早期临床效果良好。在应用ePTFE带瓣管道时应注意植入指征及术后抗凝管理,特别是带瓣管道的制备细节,以使管道植入后获得更好的功能及耐久性。

Objective:Due to the lack of large-sized pulmonary valved conduit products in clinical practice,hand-sewn expanded polytetrafluoroethylene(ePTFE)valved conduit has been used for right ventricular outflow tract(RVOT)reconstruction in many heart centers around the world.This study aims to summarize the early results of the ePTFE valved conduit and the sewing technology of the conduit in combination with the latest progress,and to provide a reference for the application of ePTFE valved conduit.Methods:A total of 21 patients using ePTFE valved conduit for RVOT reconstruction in the Second Xiangya Hospital,Central South University from October 2018 to October 2020 were prospectively enrolled in this study.The age at the implantation of the conduit was 4.3 to 43.8(median 15.1)years old,with weight of(38.9±4.1)kg.In this cohort,14 patients underwent re-reconstruction of RVOT,including 12 patients with pulmonary regurgitation at 6.3 to 31.0(median 13.8)years after tetralogy of Fallot(TOF)repair,and 2 patients with failed bovine jugular vein conduit(BJVC).Seven patients underwent Ross operations.Among them,3 were for aortic valve stenosis,2 were for aortic regurgitation,and 2 were for both stenosis and regurgitation.The ePTFE valved conduits were standard hand-sewn during the surgery.The 3 leaflets were equal in size with arc-shaped lower edge of the valve sinus.The free edge of the valve leaflets was straight with the length of about 1 mm longer than the diameter.The height of the valve sinus was 4/5 of the diameter.The junction of the valve leaflet was 3/4 of the height of the sinus.The designed leaflets were then continuous non-penetrating sutured into the inner surface of Gore-Tex vessel to make a valved conduit.Valved conduits with diameter of 18,20,and 22 mm were used in 2,9,and 10 cases,respectively.The surgical results,postoperative recovery time,and serious complications were summarized,and the changes of postoperative cardiac function status and hemodynamic status of the conduits were investigated.Results:During the implantation of ePTFE valved conduit for RVOT reconstruction,2 patients underwent mechanical mitral valve replacement with Ross operation,2 patients with pulmonary regurgitation with repaired TOF underwent left and right pulmonary artery angioplasty,and 1 patient with failed BJVC underwent tricuspid valvuloplasty.The cardiopulmonary bypassing time for patients underwent re-reconstruction of RVOT was(130.9±16.9)min,with aorta clamping for 1 patient to repair the residual defect of the ventricular septum.The cardiopulmonary bypassing and aorta clamping time for Ross operation were(242.7±20.6)min and(145.6±10.5)min,respectively.The duration of postoperative ventilator assistance,intensive care unit stay,and hospital stay were 3.5 h to7.7 d(median 17.1 h),11.2 h to 29.5 d(median 1.9 d),and 6.0 to 56.0(median 13.0)d,respectively.All patients survived after discharge from hospital.The follow-up rate after discharge was 100%with median time at 15.0(13.0 to 39.0)months.No death happened during the follow-up.One patient underwent stent implantation due to right coronary stenosis 2 months after Ross operation.One patient underwent balloon dilation due to right pulmonary artery ostium stenosis 1 year after re-reconstruction of RVOT.The cardiac function of all patients recovered to NYHA class I 6 months after operation.The peak pressure gradient across the valve measured by transthoracic echocardiography before discharge was(9.4±2.6)mm Hg(1 mm Hg=0.133 k Pa),and(18.3±6.1)mm Hg at the last follow-up.There was no significant increase in the gradient during the follow-up(P=0.134).No patient suffered from mild or more pulmonary regurgitation.Conclusion:Hand-sewn ePTFE valved conduit is feasible for RVOT reconstruction.It is a promising material for RVOT reconstruction which can effectively meet clinical need.In our experience,the ePTFE valved conduit is simple to manufacture with satisfactory early outcomes.In the application of ePTFE valved conduit,attention should be paid to implantation indications and postoperative anticoagulation management,especially to the preparation details of the valved conduit,to obtain better function and durability of the conduit after implantation.