Shemin R J, Schoen F J, Hein R, Austin J, Cohn L H
Department of Surgery, Brigham and Women's Hospital, Boston, Mass.
J Thorac Cardiovasc Surg. 1988 May;95(5):912-9.
This study investigated the in vivo hemodynamics and pathologic changes of a unileaflet pericardial bioprosthetic valve 3 to 5 months after implantation in juvenile sheep. Group 1 had 10 sheep with tricuspid valve replacement. Group 2 had nine sheep with mitral valve replacement. Group 3 served as a control with 10 sheep that had tricuspid valve replacement with a trileaflet porcine bioprosthesis. Hemodynamic performance was satisfactory in all three groups despite prominent pathologic changes, particularly in unileaflet valves. Intrinsic cuspal calcification was present in 66% of the unileaflet tricuspid, 88% unileaflet mitral, and 25% porcine tricuspid valves. Neither cuspal tearing nor perforations were found. However, cuspal stretching and redundancy of the mobile cusp was present in six tricuspid, seven mitral unileaflet valves, and no porcine valves. Gross pericardial redundancy correlated with the microscopic appearance of distorted and separated collagen bundles. These findings suggest that multiple modes of primary tissue failure may limit the durability of this unileaflet pericardial valve.
本研究调查了青少年绵羊植入单叶心包生物瓣膜3至5个月后的体内血流动力学和病理变化。第1组有10只接受三尖瓣置换的绵羊。第2组有9只接受二尖瓣置换的绵羊。第3组作为对照组，有10只接受三叶猪生物瓣膜三尖瓣置换的绵羊。尽管有明显的病理变化，特别是在单叶瓣膜中，但所有三组的血流动力学性能均令人满意。66%的单叶三尖瓣、88%的单叶二尖瓣和25%的猪三尖瓣存在固有瓣叶钙化。未发现瓣叶撕裂或穿孔。然而，6个三尖瓣、7个单叶二尖瓣存在瓣叶伸展和活动瓣叶冗余，而猪瓣膜未出现。心包明显冗余与胶原束扭曲和分离的微观表现相关。这些发现表明，多种原发性组织衰竭模式可能会限制这种单叶心包瓣膜的耐久性。
