RESUMO
In order to assess the transvalvular gradient of a Chinese-made Jiuling solid pyrolytic carbon bileaflet heart valve prosthesis, we determined its hydrodynamics in the laboratory and then measured the hemodynamic performance in the animals and patiens. The Jiuling prosthesis was tested in a pulsatile flow simulator in the aortic position. Six sheep subjected to mitral replacement with 21 mm Jiuling prosthesis were measured by open cardiac catheterization intraoperatively. Doppler echocardiography and open cardiac catheterization under dobutamine stress were performed in two sheep 60 months after implantation. Clinically, 14 cases of aortic valve and 10 cases of mitral valve in the patients who underwent valve replacement with Jiuling heart valve prosthesis were measured by open cardiac catheterization and Doppler echocardiopgraphy. The results showed that Juiling heart valve prosthesis had lower mean transvalvular gradient (below 10 mmHg) at any given tissue annulus diameter. In animal experiments, the transvalvular gradients of 6 sheep were 5.2 +/- 1.7 mmHg intraoperatively, and of 2 sheep 60 months after implantation were 6.1 +/- 0.3 mmHg by catheterization. In patients, the mean transvalvular gradients in the aortic position measured by means of catheterization and echocardiography were 6.26-4.10 mmHg and 9.42-7.48 mmHg; the gradients in the mitral position were 2.10-1.9 mmHg and 5.281-4.10 mmHg respectively. The above results demonstrate that Jiuling valve prosthesis has excellent hemodynamic performance.