Rheumatic heart valve disease (RHVD) is a post-infectious sequel of acute rheumatic fever resulting from an abnormal immune response to a streptococcal pharyngitis that triggers valvular damage. RHVD is the leading cause of cardiovascular death in children and young adults, mainly in women from low and middle-income countries. It is known that long-term inflammation and high degree of fibrosis leads to valve dysfunction due to anatomic disruption of the valve apparatus.in low and middle-income countries, rheumatic heart valve disease (RHVD) is the leading cause of cardiovascular death in children and young adults When there is severe valvular dysfunction, especially if the patient is symptomatic, surgery is indicated. (1)Traditional mitral valve surgery via a median sternotomy is safe and effective, but it results in a high degree of trauma and a long incision.(2) In the last 2 decades, a minimally invasive (MI) technique has been used widely in cardiac surgery.(3-4) Its prominent advantage in post-surgery recovery and the small incision required makes patients prefer it over a traditional incision.(5-6) Patients underwent Minimal invasive surgery after intravenous anaesthesia combined with general anaesthesia, and their right side was elevated at 30°. After disinfection and draping were performed with sterile protective film fixed to it. Establishing the in vitro pathway: First, venous and arterial access was established. Incision establishment: A 4 to 6 cm incision was opened layer by layer in the chest anterolaterally to the right of the fourth intercostal space (in submamarry vs. peri areolar approach ). A lap-protector was placed. The thoracoscope was inserted near the anterior axillary line of the third intercostal space into the chest with CO2 input. A pericardial longitudinal incision was made under direct vision, extending to the head side and reflexed when reaching the aorta, with the pericardium suspended. Extracorporeal circulation was started, and Chitwood occlusion forceps were inserted into the chest to block the ascending aorta through the fourth intercostal space; the drainage tube of the left atrium perforated the chest through the right midaxillary line between the fifth and sixth intercostal space. 4-0 Prolene was used for the purse-string suturing of the cardioplegia cannula and antegradecardioplegia fluid was performed. After electrocardiograph monitoring showed that electrocardiac activity had stopped, the interatrial groove was freed, the left atrial incision was made parallel to the interatrial groove, and the left atrial drainage tube was inserted. A left atrial retractor was placed and stretched to the surface for fixation through the perforation into the prothorax, and the left atrial incision was retracted in the direction of the sternum. Removal of the damaged mitral valve by endoscopic surgical instruments, and the mitral valve was sutured intermittently. After examination of the valve location and the opening and closing performance of the valve leaf, the left atrial incision was sutured continuously by prolene 4/0. Retrograde cardioplegia perfusion through the tube was initiated for venting and rewarming of the patient started, and the anesthesiologist ventilated the lungs with air to keep the lung lobes full and to relieve the occlusion of the ascending aorta. Cardiopulmonary bypass was stopped gradually and bleeding was stopped; a chest drainage tube was inserted through the hole for the left atrium drainage tube, and the chest was closed.