ObjectiveTo evaluate the early and mid-term outcomes of GK bileaflet mechanical valve applied in mitral valve replacement. MethodsTwenty patients with rheumatic mitral stenosis underwent mitral valve replacement in our hospital from March 2008 to June 2011. Ten patients of them chose GK bileaflet mechanical valve for surgery (a GK group, 5 males and 5 females, aged 56.4±8.9 years), while the other 10 patients chose Medtronic Open Pivot mechanical valve (a Medtronic group, 4 males and 6 females, aged 50.2±8.0 years). The preoperative, perioperative and postoperative data were analyzed and compared between the two groups. Cardiac CT angiography (CTA) and transesophageal echocardiography (TEE) were performed to evaluate leaflets opening angle, the morphological features of the mechanical valve and the hemodynamic features in the third year after surgery during the follow-up. ResultsNo mortality, defect, low cardiac output syndrome or bleeding after surgery occurred in either group. The result of 3-year follow-up showed that the function of the mechanical valve showed no difference between the two groups. Cardiac CTA and TEE showed good morphological features in all patients. ConclusionThe GK bileaflet mechanical valve has equivalent effect as Medtronic Open Pivot mechanical valve for mitral valve replacement during the 3-year follow-up.