Double-crowned valved stents for off-pump mitral valve replacement
Double-crowned valved stents for off-pump mitral valve replacement
复制标题
DOI：
10.1016/j.ejcts.2004.12.068
复制
发表时间：
2005-08-01
影响因子：
3.4
通讯作者：
von Segesser, LK
中科院分区：
文献类型：
--
作者：
Ma, L;Tozzi, P;von Segesser, LK
设计了动物模型来评估使用带瓣膜支架进行非体外循环二尖瓣置换术的可行性。方法：将戊二醛保存的同种移植物缝合在假体管（涤纶）内。然后，将两个自膨式镍钛合金Z型支架缝合在假体的外表面上，形成两个自膨式牙冠进行固定。在成年猪中，在全身麻醉下，通过左胸廓切开术暴露左心房，并通过血管内超声 (IVUS) 和透视进行房室路线图绘制。将双冠带瓣膜支架装入输送鞘中。然后将鞘管引入左心房，并将带瓣膜支架展开在二尖瓣位置，使得两个支架之间的部分位于二尖瓣水平。环。心内超声（ICUS）用于评估瓣膜功能。还收集了血流动力学参数。在进行左心瓣膜展开和大体解剖检查后，动物存活不超过3小时。结果：带瓣支架的平均高度为29.4+/-0.2mm，内径为20.4+/-1.0mm，外径为25.5+/-0.8mm。该程序在八只动物身上成功进行。体内评估显示天然二尖瓣环直径为 24.9 +/- 0.6 mm，平均二尖瓣面积为 421.4 +/- 17.5 mm(2)。 ICUS 显示轻度二尖瓣。八只动物中有三只出现反流。带瓣膜支架的平均压力梯度为 2.6 +/- 3.1 mmHg。左心室流出道 (LVOT) 的平均压力梯度为 6.6 +/- 5.2 mmHg。平均生存时间为 97.5 +/- 56.3 分钟（生存时间范围为 40-180 分钟）。一只动物因带瓣膜支架移位导致 LVOT 闭塞而死亡。尸检评估证实八只动物中的七只带瓣膜支架正确定位在二尖瓣位置。无心房。或发现由于带瓣膜支架引起的脑室病变。结论：在二尖瓣位置非体外循环植入自膨式带瓣支架在技术上是可行的。进一步的研究将评估该程序是否也适用于人类。 (c)) 2005 Elsevier B.V. 保留所有权利。
An animal model has been designed to assess the feasibility of off-pump mitral valve replacement using valved stents. Methods: Glutaraldehyde-preserved homograft was sutured inside a prosthetic tube (Dacron). Then, two self-expandable nitinol Z-stents were sutured on the external surface of the prosthesis in such a way to create two self-expanding crowns for fixation. In adult pigs and under general anesthesia, the left atrium was exposed through a left thoracotomy and atrio-ventricutar roadmapping was performed with intravascular ultrasound (IVUS) and fluoroscopy. The double-crowned valved stents were loaded into a delivery sheath. The sheath was then introduced into the left atrium and the valved stents was deployed in mitral position in such a way that the part in between the two stents was at the level of the mitral. annulus. Intracardiac Unltrasound (ICUS) was used to assess the valve function. Hemodynamic parameters were gathered as well. Animal survived for no more than 3 h after the valve deployment and gross anatomy examination of the left heart was carried out. Results: The mean height of the valved stents was 29.4 +/- 0.2 mm, with an internal diameter of 20.4 +/- 1.0 mm, and an external diameter of 25.5 +/- 0.8 mm. The procedure was successfully carried out in eight animals. In vivo evaluation showed a native mitral annulus diameter of 24.9 +/- 0.6 mm, and a mean mitral valve area of 421.4 +/- 17.5 mm(2). ICUS showed a mild mitral. regurgitation in three out of eight animals. Mean pressure gradient across the valved stents was 2.6 +/- 3.1 mmHg. Mean pressure gradient across the left ventricular outflow tract (LVOT) was 6.6 +/- 5.2 mmHg. The mean survival time was 97.5 +/- 56.3 min (survival time range was 40-180 min). One animal died due to the occlusion of the LVOT because of valved stents displacement. Postmortem evaluation confirmed correct positioning of the valved stent in the mitral position in seven out of eight animals. No atrial. or ventricutar lesions due to the valved stents were found. Conclusions: Off-pump implantation of a self-expandable valved stent in the mitral position is technically feasible. Further studies will assess if this procedure is also feasible in humans. (c)) 2005 Elsevier B.V. All rights reserved.