Valve Selection in End-Stage Renal Disease: Should It Always Be Biological?

BACKGROUND: When valve replacement is required in patients with end-stage renal disease (ESRD), it is not clear if mechanical or bioprosthetic valve selection is better. We compared outcomes between ESRD patients who underwent either mechanical or biologic valve replacements at our institution.

METHODS: All patients with ESRD who underwent either mitral or aortic valve replacement from 2002 to 2014 at our institution were reviewed (n = 215; mechanical = 64, biological = 151). A Cox proportional hazards model was used to test the hypothesis that a mechanical valve was correlated with improved long-term survival. Among patients younger than 65 years (n = 123) we also compared survival with the Kaplan-Meier method.

RESULTS: Similar unadjusted survival was found for patients who received either a bioprosthetic or mechanical valve (log-rank p = 0.55). Survival is clearly attenuated in this patient population, with only about half the patients younger than 65 years surviving beyond 2 years. In the proportional hazards model, a mechanical valve was not correlated with improved survival even when controlled for other variables, including shock, endocarditis, mitral valve replacement, and patient age (95% confidence interval for hazard ratio of mechanical valve: 0.64 to 1.62).

CONCLUSIONS: It appears that there is minimal difference in survival after operation for ESRD patients who undergo bioprosthetic or mechanical valve replacement, even in patients younger than 65 years. The attenuated survival of the ESRD population after valve replacement makes the increased burden of anticoagulation (particularly in hemodialysis patients) unattractive. It is likely that only a small portion of ESRD patients benefit from the increased durability of a mechanical valve.