OBJECTIVE To evaluate the risk factors of tricuspid regurgitation (TR) after left-sided valve replacement (LSVR) and plan the initial surgical treatment of TR. METHODS Two hundred and forty-eight patients, including 217 patients in the LSVR group and 31 patients in the LSVR+DeVega group, were followed up. A retrospective analysis was performed on 14 characteristics in the LSVR group. Variables were used to evaluate predictors of TR progression after single LSVR by either a univariate or multivariate analysis. DeVega's tricuspid annuloplasty was evaluated on progress of TR by univariate analysis. RESULTS The mean follow-up was 5.2 +/- 2.9 (range, 3-16) years after surgery. In a univariate analysis, atrial fibrillation, huge left atrium, long time from onset to surgery, tricuspid rheumatic changes, preoperative +2 or +3 TR, the degradation of left ventricular ejection fraction, augmented right atrium, and single mitral valvular disease were significant risk factors for TR development. A multivariate analysis indicated that the four items mentioned above were statistically significant predictors of TR after surgery. The progress of TR in the LSVR+DeVega group was significantly less than in the LSVR group. CONCLUSIONS An aggressive repair of accompanying TR should be performed at the time of initial surgery in patients with a huge left atrium, atrial fibrillation, long time from onset to surgery, or tricuspid rheumatic changes. DeVega's tricuspid annuloplasty therefore helps prevent a progression of TR.