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Objective To investigate the influence of different angles between the ventricular flow chamber and the aortic lumen on the mechanical performance of aortic valve. Methods Based on the angles of ventricular flow in CT images obtained from Wuhan Union Hospital, three models of aortic root with different angles (0°, 16. 5°, 30°) of ventricular flow chamber were manufactured by using 3 D printing technique.Artificial bioprosthetic valve was assembled in the aortic models, and experiments of pulsatile flow in a simulation system of pulsatile circulation were performed under different cardiac output conditions. The heart rate was 70 times/min, and the flow rates of pulsatile flow were 2, 3, 4, 5, 6, 7 L/min respectively. In this condition, the transvalvular pressure gradients, the regurgitation fraction and effective orifice area were measured. The tests were carried out for ten times under each pulsatile flow condition, and the mean values of the ten tests were obtained for the final result. Results The transvalvular pressure gradients for the heart valve prosthesis models with different angles of ventricular flow chamber were different, yet all of them satisfied thestandard and less than 10 mmHg. For the case of low cardiac output, smaller angle of ventricular flow chamber facilitated the decrease of the regurgitation fraction, while larger angle of ventricular flow chamber facilitated the increase of the effective valve orifice area; for the case of high cardiac output, smaller angle of ventricular flow chamber facilitated the increase of the effective valve orifice area. Conclusions Surgeons can select applicable angle of ventricular flow chamber according to the patient parameters.