Department of Cardiovascular Surgery, Second Xiangya Hospital, Central South University, Changsha 410011.
Engineering Laboratory of Hunan Province for Cardiovascular Biomaterials, Changsha 410011.
Zhong Nan Da Xue Xue Bao Yi Xue Ban. 2022 Jan 28;47(1):94-100. doi: 10.11817/j.issn.1672-7347.2022.200926.
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.
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.
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 to 7.7 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) mmHg (1 mmHg=0.133 kPa), and (18.3±6.1) mmHg at the last follow-up. There was no significant increase in the gradient during the follow-up (=0.134). No patient suffered from mild or more pulmonary regurgitation.
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.
由于临床实践中缺乏大尺寸肺动脉带瓣管道产品，许多心脏中心已将手工缝制的膨体聚四氟乙烯（ePTFE）带瓣管道用于右心室流出道（RVOT）重建。本研究旨在总结 ePTFE 带瓣管道及其与最新进展相结合的管道缝合技术的早期结果，并为 ePTFE 带瓣管道的应用提供参考。
中南大学湘雅二医院 2018 年 10 月至 2020 年 10 月期间前瞻性纳入 21 例使用 ePTFE 带瓣管道行 RVOT 重建的患者。带瓣管道植入时的年龄为 4.3 至 43.8 岁（中位数 15.1 岁），体重为（38.9±4.1）kg。在该队列中，14 例患者行 RVOT 再重建，包括 12 例在法洛四联症（TOF）修复后 6.3 至 31.0 年（中位数 13.8 年）出现肺动脉瓣反流，2 例牛颈静脉带瓣管道（BJVC）失败。7 例患者行 Ross 手术。其中，3 例为主动脉瓣狭窄，2 例为主动脉瓣反流，2 例为狭窄和反流。术中标准手工缝制 ePTFE 带瓣管道。3 个瓣叶大小相等，瓣窦下边缘呈弧形。瓣叶游离缘为直形，长约 1mm 长于直径。瓣窦高度为直径的 4/5。瓣叶交界处为窦高度的 3/4。然后将设计好的瓣叶连续非穿透缝合到 Gore-Tex 血管内，形成带瓣管道。2 例、9 例和 10 例分别使用直径为 18、20 和 22mm 的带瓣管道。总结手术结果、术后恢复时间和严重并发症，观察术后心功能状态和管道血流动力学变化。
在 RVOT 重建中植入 ePTFE 带瓣管道时，2 例患者行 Ross 手术时行机械二尖瓣置换，2 例 TOF 修复后肺动脉瓣反流患者行左右肺动脉扩张，1 例 BJVC 失败患者行三尖瓣瓣成形术。行 RVOT 再重建的患者体外循环时间为（130.9±16.9）min，其中 1 例患者因残留室间隔缺损需行主动脉阻断。行 Ross 手术的患者体外循环时间和主动脉阻断时间分别为（242.7±20.6）min 和（145.6±10.5）min。术后呼吸机辅助时间、重症监护病房停留时间和住院时间分别为 3.5 至 7.7d（中位数 17.1h）、11.2h 至 29.5d（中位数 1.9d）和 6.0 至 56.0d（中位数 13.0d）。所有患者出院后均存活。出院后随访率为 100%，中位随访时间为 15.0（13.0 至 39.0）个月。随访期间无死亡病例。1 例患者在 Ross 手术后 2 个月因右冠状动脉狭窄行支架植入术，1 例患者在 RVOT 再重建后 1 年因右肺动脉口狭窄行球囊扩张术。所有患者术后 6 个月心功能均恢复至 NYHA Ⅰ级。出院前经胸超声心动图测量的瓣口峰值压力梯度为（9.4±2.6）mmHg（1mmHg=0.133kPa），末次随访时为（18.3±6.1）mmHg，随访期间无明显升高（=0.134）。无患者出现轻或更严重的肺动脉瓣反流。
手工缝制的 ePTFE 带瓣管道用于 RVOT 重建是可行的。它是一种有前途的 RVOT 重建材料，可以有效满足临床需求。根据我们的经验，ePTFE 带瓣管道制造简单，早期结果令人满意。在 ePTFE 带瓣管道的应用中，应注意植入指征和术后抗凝管理，特别是带瓣管道的准备细节，以获得更好的功能和耐久性。
