Influence of percutaneous mitral valve repair using the MitraClip® system on renal function in patients with severe mitral regurgitation

Background: In patients with mitral regurgitation (MR), changes in cardiac stroke volume, and thus renal preload and afterload may affect kidney function. Percutaneous mitral valve repair (PMVR) with the MitraClip® system can be a therapeutic alternative to surgical valve repair. The influence of MitraClip® therapy on renal function and clinical outcome parameters is unknown. Methods and Results: Sixty patients with severe MR underwent PMVR using the MitraClip® system in an open‐label observational study. Patients were stratified according to their renal function. All clips have been implanted successfully. Effective reduction of MR by 2–3 grades acutely improved KDOQI class. Lesser MR reduction (MR reduction of 0–1 grades) led to worsening of renal function in patients with pre‐existing normal or mild (KDOQI 1–2) compared to severe (KDOQI 3–4) renal dysfunction. Reduction of MR was associated with improvement in Minnesota Living with Heart Failure Questionnaire (MLHFQ), NYHA‐stadium, and 6‐minute walk test. Conclusion: Successful PMVR was associated with an improvement in renal function. The improvement in renal function was associated with the extent of MR reduction and pre‐existing kidney dysfunction. Our data emphasize the relevance of PVMR to stabilize the cardiorenal axis in patients with severe MR. © 2014 Wiley Periodicals, Inc.