Trial On The Long-term Stability Of Bovine Pericardium After Chemical Modified Effects And Evaluation On The Clinical Hemodynamics Of Perfeot Bovine Valve And Its Long-term Follow-up Results

Bioprosthetic heart valve is liable to retrograde affection and calcification, which effects its durability seriously, limits its further development and wide application. It is understood that the durability of bioprosthetic heart valve can be improved by the methods of chemical modified effects on biological material, strengthening tissue material. Reducing calcification, improving the design of valve and sewing method, strengthening the elasticity of valve stent and reducing the abrasion of valve leaf against stent are also helpful.1. Experimental study on the long-term stability of modified bovine pericardium.The phenomenon of loosing cross-link can appear after the glutoraldehyde (GA) cross-linking bioprosthetic heart valve is implanted into human bodies. The long-term stability of hydroxyl chromium (HC) cross-linking bioprosthetic heart valve is also valuable for us to probe. Bovine pericardium modified by GA and HC were chosen in this project. They were stored in different storage buffers (0.3%GA, 4% formaldehyde and isotonic Na₂SO₄ solution ) and control buffers ( physiological saline and fresh human plasma ). Overall evaluation were made separately on the shrinkage temperature , tissue humidity, thickening rate,...