Background: the "forgotten valve" or "lost valve," as the tricuspid valve has received less attention as important as the other heart valves,. The prevalence of functional tricuspid regurgitation (FTR) has been reported to reach 25% to 30%, with left-sided valvular heart lesions. Aim of the work: to evaluate the Impact of moderate tricuspid valve regurgitation repair during rheumatic mitral valve surgery at midterm results. Patients and Methods: 60 patients were selected in our prospective randomized comparative study, by simple random sampling, which done between February 2018 and June 2020 at cardiothoracic surgery department at Zagazig University hospitals in Egypt. Two groups were created,30 patients were randomly assigned to Group I (Repair group), where they received mitral valve surgery and tricuspid valve repair using pericardial band, and 30 patients were randomly assigned to Group II (No-repair group), where they underwent mitral valve surgery alone. Results: Our research found a statistically significant difference in terms of echo findings at discharge, 6 months, and 18 months follow-up, with higher progression of the degree of tricuspid regurgitation being detected in the no-repair group compared to the repair group. Rehospitalization from congestive heart failure and the requirement for tricuspid valve reintervention are also significantly higher in the no-repair group. Conclusion: In patients with moderate functional tricuspid regurgitation undergoing rheumatic mitral valve surgery, repair of the tricuspid valve with pericardial band is recommended because it is associated with less statistically significant progression in echo findings of the degree of tricuspid regurgitation, rehospitalization due to C.H.F. and tricuspid valve reintervention compared to no-repair group at midterm results.

functional moderate tricuspid regurgitation, surgical repair, rheumatic mitral valve surgery