Sung H W, Witzel T H, Hata C, Tu R, Shen S H, Lin D, Noishiki Y, Tomizawa Y, Quijano R C
Baxter Edwards CVS Division, Irvine, California.
Int J Artif Organs. 1993 Apr;16(4):199-204.
Many congenital cardiac malformations may require a valved conduit for the reconstruction of the right ventricular outflow tract. In spite of many endeavors made in the last 25 years, the clinical results of right ventricular outflow tract reconstruction with currently available valved conduits are still not satisfactory. Specific problems encountered clinically include suboptimal hemodynamic performance, conduit kinking or compression, and fibrous peeling from the luminal surface. To address these deficiencies, we undertook the development of a biological valved conduit: a bovine external jugular vein graft with a retained native valve cross-linked with a diglycidyl ether (DE). This study, using a canine model, was to evaluate the functional and hemodynamic performance of this newly developed valved conduit. Three 14 mm conduits, implanted as bypass grafts, right ventricle to pulmonary artery, were evaluated. The evaluation was conducted with a noninvasive color Doppler flow mapping system at pre-implantation, immediately post implantation, one- and three-months post implantation, and prior to retrieval (five-months post implantation). The two-dimensional tomographic inspection of the leaflet motion at various periods post implantation showed that the valvular leaflets in the DE treated conduit was quite pliable. No cardiac failure or valvular dysfunction was observed in any of the studied cases. The color Doppler flow mapping study demonstrated that the valve in the DE treated conduit was competent, with no conduit kinking or compression observed in any of the three cases. The spectral Doppler velocity study evidenced that the transvalvular pressure gradients of the DE treated conduit were minimal as compared to those of the currently available conduits. In conclusion, from the functional and hemodynamic performance points of view, this newly developed valved conduit is superior to those currently available.
许多先天性心脏畸形可能需要带瓣管道来重建右心室流出道。尽管在过去25年里人们付出了诸多努力，但使用现有带瓣管道进行右心室流出道重建的临床效果仍不尽人意。临床上遇到的具体问题包括血流动力学性能欠佳、管道扭结或受压以及管腔内表面纤维剥脱。为解决这些不足，我们着手研发一种生物带瓣管道：一种保留天然瓣膜的牛颈外静脉移植物，并用二缩水甘油醚（DE）进行交联。本研究采用犬模型，旨在评估这种新研发的带瓣管道的功能和血流动力学性能。评估了三根作为右心室到肺动脉旁路移植物植入的14毫米管道。在植入前、植入后即刻、植入后1个月和3个月以及取出前（植入后5个月），使用无创彩色多普勒血流成像系统进行评估。植入后不同时期对瓣叶运动的二维断层检查显示，经DE处理的管道中的瓣叶相当柔韧。在所研究的任何病例中均未观察到心力衰竭或瓣膜功能障碍。彩色多普勒血流成像研究表明，经DE处理的管道中的瓣膜功能正常，在三个病例中均未观察到管道扭结或受压。频谱多普勒速度研究证明，与现有管道相比，经DE处理的管道的跨瓣压力梯度最小。总之，从功能和血流动力学性能的角度来看，这种新研发的带瓣管道优于现有管道。
