Abstract 16515: Mitral Regurgitation Severity is Associated with Renal Function: Post-Hoc Analysis of the EVEREST II Trials of Transcatheter Mitral Valve Repair
Introduction: The relationship between mitral regurgitation (MR) severity and renal function has not been described. It is hypothesized that a reduction of MR following the MitraClip procedure is associated with improved renal function.
Methods: Patients enrolled in the EVEREST II Randomized Controlled Trial (n=178) and high surgical risk patients from the EVEREST II High Risk Study (N=78) and REALISM Continued Access Study (n=133) with baseline moderate-to-severe or severe (3+/4+) MR and treated with the MitraClip device were evaluated. Creatinine clearance (CrCl) was calculated by Cockcroft-Gault normalized to body surface area and quantitative MR severity by American Society of Echocardiography criteria were evaluated. Linear mixed modeling was performed to evaluate the relationship between MR severity (grade 3+ or 4+ vs 1+ or 2+) and CrCl. Both measures were collected at baseline, 30 days, 6 months and 12 months (n=1,335 data points). Separate models were fit for patients with and without severe renal dysfunction (CrCl <30 ml/min).
Results: Of the 382 patients with available CrCl at baseline, 142 (37%) had CrCl >60 ml/min; 168 (44%) had CrCl 30-60 ml/min; and 72 (19%) had CrCl <30 ml/min. In 45 patients with CrCl <30 ml/min at baseline, 15 (33%) patients had increase in CrCl to ≥30 ml/min at 1 year. Severity of MR was significantly associated with relative change in CrCl for patients with baseline CrCl <30 ml/min (p=0.0011) as well as baseline CrCl ≥30 ml/min (p<0.0001). In patients with severe renal dysfunction, reduction in MR to ≤2+ at 1 year was associated with a 30% increase in CrCl (p=0.004). MR etiology (degenerative or functional) was not associated with relative change in renal function.
Conclusions: Reduction in MR severity with the MitraClip system is strongly associated with improvement in renal function in patients with severe renal dysfunction.
- © 2012 by American Heart Association, Inc.