2014-08-012024-05-14https://scholars.lib.ntu.edu.tw/handle/123456789/660766摘要：右心室出口重建 (Right Ventricular Outflow Tract Reconstruction) 是複雜性先天性心臟病常見的術式之一。由於病人年齡小、體重輕，沒有合適的瓣膜可供使用，長期肺動脈瓣閉鎖不全 (或逆流) 導致右心室擴大、功能衰竭，必須置放瓣膜，但生物性瓣膜 (xenograft prostheses) 在青春期及懷孕期易造成瓣膜組織退化及鈣化破損，而人工機械性瓣膜 (mechanical prostheses) 易形成血栓，必須使用抗凝劑，其容易引發出血，且有畸胎的副作用，所以尋求較佳、且易得的替代品，成為一大課題。Expended polytetra fluoroethylene (ePTFE) 已被證實具有良好的生物相容性 (biocompatibility)，其微孔但不易溶漏的構造可防止細胞的穿透及後續的鈣化現象，早已被使用於發紺性的先天性心臟病之分流術 (syotemico-pulmonary shunts) 及右心室出口補片重建術。亦有數種帶瓣人工血管之使用，但製作過程繁瑣。我們發展一種手工縫製容易 (可於廿分鐘內完成) 且具有閥氏竇 (Sinus of Valsalva) 功能的帶瓣人工血管，過去兩年臨床使用於 15 位病人得到良好的結果 (包括心臟超音波之追踪)。由於製作材料簡單，縫線較其他做法少，可能可進一步發展成為經皮及導管置放術 (transcatheter pulmonary valvular replacement)，唯需先有其流體力學之工程測試 (Engineering assessments)，故設計本實驗以茲證明其效用，並冀望可推廣使用。 本研究取 16mm、18 mm、20 mm、22 mm 及 24 mm 五種內徑之 ePTFE 人工血管依計劃內容所附之瓣膜縫製法，並製造 Sinus of Valsalva，將其縫製在一個仿製人工循環管路 (circulatory mock loop system)，其經過瓣膜噴出之血流模式 (dowstream flow field velocity)，利用 digital particle image velocimetry (DPIV) 來測量。而其瓣膜之開合則利用一組三稜鏡銜接至一 high speed camera (PIVCAM 10-30 CCD video camera)，捕捉 1000 frames/second 的瓣膜開合影像，每種 size 製作三個，重複測試，以彌平手縫所產生之差異性。並比較不同大小管徑所造成之影響。其 sinus vortices flow 則利用病人在已術後每半年追踪超音波的影像中測量。<br> Abstract: Primary right ventricular outflow tract (RVOT) reconstruction is one of the most distinctive procedures in the complex congenital heart surgery. Since that patients were young and small, there was no proper pulmonary valvular prosthesis available for implantation. Long-term pulmonary valve insufficiency or regurgitation leads right ventricle dilation and right heart failure. Pulmonary valve replacement (PVR) became inevitable. However, the homograft or xenografts easily degenerate and calcify in the adolescents and child-bearing female patients. In the other hand, Anticoagulant therapy is essential to prevent thrombogenesis for mechanical prostheses, but it usually ends up with adverse effects, such as bleeding and teratogenic effects. Expanded polytetrafluoroethylene (ePTFE) has been documented with good biocompatibility and its microporous structure impedes cellular penestration and subsequent calcification. The product has been widely used as graft for systemico-pulmonary shunts and primary RVOT patch reconstruction in cyanotic congenital heart surgery. Various ePTFE valved conduits have been used but the methods and conduct processes were complicated. We have created an efficient way to make a trileaflet-valved conduit of ePTFE with sinus of Valsalva function for PVR. In the past two years, it has been implanted in 15 patients with satisfactory results in clinical follow-up by echocardiography.Because of the simpler design with less suture length comparing to other methods, it may be feasiblel for further transcatheter PVR. Engineering assessments will be helpful for better and broader application. In the study, five different sizes of ePTFE vascular grafts (16 mm, 18 mm, 20 mm, 22 mm and 24 mm) were included. They will be made by the method published in a well-known medical journal (The Annals of Thoracic Surgery). We will mount these conduits to a glassed tube with sinuses of Valsalva, connected to a circulatory mock loop system. The downstream flow field velocity will be measured by digital particle image velocimetry (DPIV). The movement of the valved conduits will be inspected and recorded through a viewing window at 1000 frames/s and tracked by a high speed camera (PIVCAM 10-30 CCD video camera). Each sized valved conduit will be repeated by three brand new hand-made ones to dissipate the minor suture error. The sinus vortices flow will be detected by echocardiography in those patients implanted with the valved conduits.