Background: Concomitant tricuspid valve repair (TVr) for functional tricuspid regurgitation (TR) at the time of leftsided valve surgery has become increasingly more common over the past decade. The impact of residual post-repair TR on late outcomes remains unclear. Methods: All patients undergoing TVr during concomitant left-sided valve surgery at our institution from 2005- 2012 were retrospectively reviewed. Patients were stratified into 2 groups according to the degree of post-cardiopulmonary bypass TR observed on intraoperative transesophageal echocardiography; 0-1+ TR (No TR, n = 246) and ?2+ TR (Residual TR, n = 26). Primary outcomes of interest were 30-day survival, 4-year survival, and follow-up TR grade. A propensity-matched subgroup analysis was performed in addition to the overall cohort analysis. Results: Mean age for all patients was 70.3 ± 13.0 years and 107 (39%) patients were male. There was no difference in 30-day survival between groups (92% No TR versus 96% Residual TR, P = .70). Kaplan-Meier analysis of overall 4-year survival showed a trend toward worsened survival in the Residual TR group (log rank P = .17) and propensitymatched subgroup analysis showed significantly worse 4-year survival for Residual TR (log rank P = .02). At mean echocardiographic follow up of 11.9 ± 22.5 months, TR grade was significantly worse in the Residual TR group compared to No TR (1.5 ± 0.8 Residual TR versus 0.9 ± 0.9 No TR, P = .005), although TR severity was significantly improved from immediately post-bypass. Conclusions: Patients left with residual TR following TVr during concomitant left-sided valve surgery have significantly decreased late survival compared to patients left with no post-repair TR.