Outcomes of Surgical Mitral and Aortic Valve Replacements Among Kidney Transplant Candidates: Implications for Valve Selection.

Background Limited literature exists that evaluated outcomes of kidney transplant-eligible patients who are having dialysis and who are undergoing valve replacement. Our main objective in this study was to compare mortality, reoperation, and bleeding episodes between bioprosthetic and mechanical valve procedures among kidney transplant-eligible patients who are having dialysis. Methods and Results We studied 887 and 1925 dialysis patients from the United States Renal Data System, who underwent mitral valve replacement and aortic valve replacement (AVR) after being waitlisted for a kidney transplant (2000-2015), respectively. Time to death, time to reoperation, and time to bleeding requiring hospitalizations were compared separately for AVR and mitral valve replacement. Kaplan-Meier survival curves, Cox proportional hazards model for time to death, accelerated time to event model for time to reoperation, and counting process model for time to recurrent bleeding were used. There were no differences in mortality (hazard ratio [HR], 0.92; 95% CI, 0.77-1.09) or risk of reoperation or risk of significant bleeding events between bioprosthetic and mechanical mitral valve replacement. However, mechanical AVR was associated with a modestly significant less hazard of death (HR, 0.83; 95% CI, 0.74-0.94) compared with bioprosthetic AVR. There were no differences in time to reoperation, or time to significant bleeding events between bioprosthetic and mechanical AVR. Conclusions For kidney transplant waitlisted patients who are on dialysis and who are undergoing surgical valve replacement, bioprosthetic and mechanical valves have comparable survival, reoperation rates, and bleeding episodes requiring hospitalizations at both mitral and aortic locations. These findings emphasize that an individualized informed decision is recommended when choosing the type of valve for this special group of patients having dialysis.