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

我们研究了两个方面，即支架置入后管腔再狭窄的预防和支架管腔的血流控制。我们研究了75例布-加综合征（45例）、5例顽固性腹水（TIPPS ; 5例）和5例颈动脉肿瘤包绕患者的支架置入术治疗效果。布-加综合征、顽固性腹水和颈动脉恶性肿瘤支架术后再狭窄率分别为15%、40%和20%。放射治疗的原发性颈部恶性肿瘤已在最后一系列的三名患者。之前的辐照可能是防止支架管腔内膜过度增生的一个因素。最近报道，在大型动物如狗中，尽管给予了大量的血管紧张素转换酶抑制剂药物，但血管紧张素II的合成没有被完全抑制。我们没有推广使用ACE抑制剂的支架植入研究。现在计划进行血管内放射治疗以保护支架腔的假内膜增生。一只狗的下腔静脉在放置Z形支架5.5年后被拔除，组织学上没有观察到侧支如肝静脉或肾静脉的闭塞。我们新开发了一种结合球囊和特殊设计的金属工具的支架腔血流控制系统。一种特殊的形状记忆合金，两侧具有两个螺旋结构，用于阻塞球囊在支架腔内的运动。用1.5TMR二维电影相衬法对聚四氟乙烯管制成的血流动力学模型进行流量测量，观察球囊置入特制合金前后的流量控制情况。

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.