The Evaluation Of In-vitro Hemodynamic Features Of Self-made Non-suturing Stentless Aortic Biological Valve

Objective This study is desinged to research a new minimally invasive aortic valve replacement surgical method with self-made new non-suturing stentless aortic biological valve,then detect the reliability of this new aortic biological valve through in-vitro experiment,and evaluate the hemodynamic features of this new aortic valve by in-vivo experiment. Methods We use the new aortic valve to establish in-vitro model of aortic valve replacement,then detect the reliability of the new aortic valve,and observe whether the new aortic valve has valve leakage surrounding,back-streaming and so on.We choose 6 Tibet miniature pigs as experimental animals,then devide them into experimental group and control group randomly,Then we implant the new aortic valve into experimental groupand and impant Medtronic Freestyle aortic biological valve into control group to establish in-vivo model of pig aortic valve replacement.The 6 Tibet miniature pigs are undertook color doppler echocardiography at the end of operation to observe the aortic valves opening and closing in experimental group and control group,and whether they have valve leakage surrounding,back-streaming and so on,then we measure the peak velocity of aortic flow spectrum,peak transvalvular pressure gradient,mean transvalvular pressure gradient,left ventricular ejection fraction,maxmium aortic valve opening area,aortic cross-clamping time,CPB time to compare the hemodynamic features differences between self-made new non-suturing stentless aortic biological valve and Medtronic Freestyle aortic biological valve.Results In in-vitro model,the self-made new non-suturing stentless aortic biological valve closes good,and do not has significant valve leakage surrounding and back-streaming,it can meet the standard of in-vivo model. In in-vivo model, color doppler echocardiography reveals that the pigs heart of experimental group and control group pulsates powerfully,rhythm is good,aortic biological valve opening and closing is good,there are no significant differences of the peak velocity of aortic flow spectrum,peak transvalvular pressure gradient,mean transvalvular pressure gradient,left ventricular ejection fraction,maxmium aortic valve opening area in experimental group and control group.The aortic cross-clamping time,CPB time in experimental group are shorter than control group. Conclusion The improved surgical method of this new minimally invasive aortic valve replacement is a more ideal surgical method.When we use self-made new non-suturing stentless aortic biological valve,it can save ortic valve replacement opertion time,and has more ideal hemodynamic features compared with Medtronic Freestyle aortic biological valve.