Special Stenting System with blood flow control and prevention of intimal hyperplasia using Angiotensin converting enzyme inhibitor

点击翻译按钮获取中文摘要

We studied two points, namely, prevention of luminal restenosis after the stent placlement and blood flow control of the stenting lumen. We have investigated the efficiency of stent placement in the treatment of the patients with Budd-Chiari syndrome (45 out of 75 patients), refractory ascites (TIPPS ; 5 patients) or tumor encasement of the cervical carotid artery (5 patients). Luminal restenosis after stenting developed in 15% of the cases of Budd-Chiari syndrome, 40% of refractory ascites and 20% of carotid artery encased by malignant tumor. Radiation therapy for the primary neck malignancy has been made in three patients in the last series. The previous irradiation could be a factor to prevent an excessive intimal hyperplasia of the stent lumen. It was recently reported that synthesis of Angiotensin II was not completely inhibited in the big animals such as dogs although a large amount of drug of Angiotensin converting enzyme inhibitor was given. We did not promote stenting study with use of ACE inhibitor. Intravascular irradiation therapy is now planned to protect pseudointimal hyperplasia of the stent lumen. No occlusion of the side branches such as hepatic veins or renal veins was histologically noticed in the inferior vena cava of a dog, extirpated after the placement of Z-stents 5.5 year later. We newly developed the controlling system of the blood flow of the stent lumen in combination of balloon and a specially designed metallic tool. A special alloy of shape-memory with two spiral structures on both sides was intended for blockage of the movement of the balloon in the stent lumen. Flow measurement of the hemodynamic model made of Teflon tube was carried out with 2D cine phase contrast method using 1.5 TMR.Flow control was observed before and after placement of balloon in the special alloy.