ObjectiveTo compare the safety and efficacy of simple mitral valve replacement with the third intercostal incision on the right side and the conventional midsternum incision.MethodsFrom February 2017 to February 2019, heart surgery in the Affiliated Hospital of Jining Medical College completed the first simple mitral valve replacement (MVR) operation in 103 patients, of whom 39 patients were received minimally invasive right third intercostal small incision (a minimally invasive surgery group). There were 10 males, 29 females at average age of 59.51 years. There were 64 patients with MVR via the middle section of the common sternum (a conventional surgery group), 22 males and 42 females, with an average age of 60.22 years. Types of lesions: 65 patients were with mitral stenosis, 22 patients with incomplete closure, 16 patients with incomplete closure.ResultsThere was no significant difference in preoperative clinical data between the two groups (P>0.05). The entire group of patients successfully completed the operation. Surgical replacement of mitral valve mechanical valve in 74 patients and biological valve in 29 patients. There was no significant difference between the two groups in the extracardiopulmonary cycle time, aortic blockade time and total hospitalization time. In the early stage of operation, 3 patients were examined for secondary hemostasis, 1 patient was minimally invasive surgery, and the remaining 2 patients were with routine surgery. The infection of incision occurred in 3 patients, all of them were in the routine operation group. All three patients died early after operation in the routine operation group: two were postoperative low cardiac volumetric syndrome leading to multiple organ failure, and the other was sternum infection accompanied by artificial valve endocarditis.ConclusionThere is no significant difference between MVR through the third rib of the right chest and traditional MVR in the safety. However, it has the advantages of small trauma, beauty, low incidence of incision infection and reduced postoperative pain.