Outcomes After Transcatheter Mitral Valve Repair in Patients With Renal Disease.

BACKGROUND: Renal disease is associated with poor prognosis despite guideline-directed cardiovascular therapy, and outcomes by sex in this population remain uncertain.

METHODS AND RESULTS: Patients (n=5213) who underwent a MitraClip procedure in the National Cardiovascular Data Registry Transcatheter Valve Therapy registry were evaluated for the primary composite outcome of all-cause mortality, stroke, and new requirement for dialysis by creatinine clearance (CrCl). Centers for Medicare and Medicaid Services-linked data were available in 63% of patients (n=3300). CrCl was <60 mL/min in 77% (n=4010) and <30 mL/min in 23% (n=1183) of the cohort. Rates of primary outcome were higher with lower CrCl (>60 mL/min, 1.4%; 30-<60 mL/min, 2.7%; <30 mL/min, 5.2%; dialysis, 7.8%; P<0.001), and all low CrCl groups were independently associated with the primary outcome (30-<60 mL/min: adjusted odds ratio, 2.32; 95% CI, 1.38-3.91; <30 mL/min: adjusted odds ratio, 4.44; 95% CI, 2.63-7.49; dialysis: adjusted hazards ratio, 4.52; 95% CI, 2.08-9.82) when compared with CrCl >60 mL/min. Rates of 1-year mortality were higher with lower CrCl (>60 mL/min, 13.2%; 30-<60 mL/min, 18.8%; <30 mL/min, 29.9%; dialysis, 32.3%; P<0.001), and all low CrCl groups were independently associated with 1-year mortality (30-<60 mL/min: adjusted hazards ratio, 1.50; 95% CI, 1.13-1.99; <30 mL/min: adjusted hazards ratio, 2.38; 95% CI, 1.78-3.20; adjusted hazards ratio: dialysis, 2.44; 95% CI, 1.66-3.57) when compared with CrCl >60 mL/min.

CONCLUSIONS: The majority of patients who undergo MitraClip have renal disease. Preprocedural renal disease is associated with poor outcomes, particularly in stage 4 or 5 renal disease where 1-year mortality is observed in nearly one-third. Studies to determine how to further optimize outcomes in this population are warranted.