Minato N, Itoh T
Department of Surgery, Saga Medical School, Japan.
J Thorac Cardiovasc Surg. 1992 Dec;104(6):1554-60.
Applying the technology of direct imaging by fiberoptic cardioscopy in a working-heart condition, we studied the tricuspid valve annular motions with flexible rings in nine dogs with chronic tricuspid regurgitation. Three annuloplasty studies with a totally flexible polytetrafluoroethylene ring, an elastic silicone ring, and a rigid metal ring were compared with a nonannuloplasty study. The annuloplasty was performed by reducing tricuspid valve annular area to 65% of that of nonannuloplasty condition. The anuli were observed and recorded on a videotape in real time. The three rings effectively reduced and remodeled the dilated anuli and improved the valve coaptation. The patterns of annular motions with the polytetrafluoroethylene and silicone ring were similar to that of normal anulus; the free wall anulus contracted centripetally, and the septal anulus moved toward the free wall side during systole. Pliability of both the anteroseptal and posteroseptal commissures with the flexible rings made these motions possible. The polytetrafluoroethylene ring followed a natural undulation of the anulus, whereas the silicone and rigid metal rings forced the annular planes to horizontal ones. Percent reductions of tricuspid valve annular area were 25%, 21%, and 23% in the nonannuloplasty, polytetrafluoroethylene, and silicone ring studies, respectively, without significant differences in annular contraction. In contrast, rigid metal rings completely disturbed the annular motions. These findings indicated that the two flexible rings did preserve the physiologic annular motions to the degree that the anuli had in the chronic tricuspid regurgitation condition. Especially, the totally flexible polytetrafluoroethylene ring preserved not only the annular motions but also the natural undulation, which resulted in reinforcing the valve coaptation. We believe that the flexible ring, especially a totally flexible one, is superior to the rigid ring in the aspect of reinforcing the valve coaptation to prevent further regurgitation.
应用纤维光学心脏镜直接成像技术，在心脏工作状态下，我们对9只患有慢性三尖瓣反流的犬进行了带有柔性环的三尖瓣环运动研究。将使用完全柔性的聚四氟乙烯环、弹性硅酮环和刚性金属环的三项瓣环成形术研究与一项非瓣环成形术研究进行了比较。瓣环成形术通过将三尖瓣环面积减小至非瓣环成形术状态下的65%来进行。实时观察瓣环并记录在录像带上。这三种环有效地缩小并重塑了扩张的瓣环，改善了瓣膜对合。聚四氟乙烯环和硅酮环的瓣环运动模式与正常瓣环相似；游离壁瓣环向心收缩，间隔瓣环在收缩期向游离壁侧移动。柔性环使前间隔和后间隔交界处具有柔韧性，从而使这些运动成为可能。聚四氟乙烯环顺应瓣环的自然波动，而硅酮环和刚性金属环则将瓣环平面强制为水平平面。在非瓣环成形术、聚四氟乙烯环和硅酮环研究中，三尖瓣环面积的减少百分比分别为25%、21%和23%，瓣环收缩无显著差异。相比之下，刚性金属环完全扰乱了瓣环运动。这些发现表明，这两种柔性环在一定程度上保留了慢性三尖瓣反流情况下瓣环的生理运动。特别是，完全柔性的聚四氟乙烯环不仅保留了瓣环运动，还保留了自然波动，这增强了瓣膜对合。我们认为，在增强瓣膜对合以防止进一步反流方面，柔性环，尤其是完全柔性的环，优于刚性环。
