Mechanical vs Bioprosthetic Aortic Valve Replacement in Patients on Dialysis: Long-term Outcomes

Using the Japan National Clinical Database and additional data, this study is an analysis of long-term survival of dialysis-dependent patients who underwent aortic valve replacement (AVR).

Dialysis-dependent patients who underwent de novo AVR between 2010 and 2012 and who were registered in the database were included. Concomitant aortic surgery and transcatheter aortic valve replacement were excluded. Additional data on the underlying kidney disease, the duration of dialysis, and clinical outcomes were registered between October 29, 2019, and August 30, 2020. The primary outcome was all-cause mortality. The secondary outcomes were cerebral infarction, cerebral bleeding, gastrointestinal bleeding, and prosthetic valve failure.

After propensity score matching, 1016 cases (508 each in the bioprosthetic and mechanical valve groups) were matched. The median follow-up period was 3.29 years (interquartile range [IQR], 0.59 years, 6.25 years). The median survival time was 5.38 years (IQR, 1.20 and 9.26 years) in the mechanical valve group and 4.98 years (IQR, 1.69 and 9.62 years) in the bioprosthetic valve group. The Cox regression model showed no significant difference in long-term survival between the groups (mechanical valve: hazard ratio [HR], 0.895; 95% CI, 0.719-1.113; P = .318). The incidences of cerebral infarction and prosthetic valve failure requiring admission were similar between the groups. Cerebral bleeding (HR, 2.143; 95% CI, 1.125-4.080; P = .002) and gastrointestinal bleeding (HR, 2.071; 95% CI, 1.243-3.451; P = .0005) were more frequent in the mechanical valve group.

Long-term survival of dialysis-dependent patients was similar regardless of whether mechanical valves or bioprosthetic valves were implanted. The incidences of cerebral and gastrointestinal bleeding were 2-fold higher in the mechanical valve group.