Impact of residual mitral regurgitation after MitraClip implantation.
BACKGROUND
MitraClip (MC) is an alternative treatment for mitral regurgitation (MR). Although residual MR is common after MC, little was known about the impact of residual MR after MC.


METHODS
We examined 255 consecutive patients who underwent MC. The primary endpoint was the composite endpoint including all-cause death, left ventricular (LV) assist device, and mitral valve surgery.


RESULTS
Procedure failure defined as unsuccessful MC implantation (n=6) and residual MR ≥3+ (n=19) was associated with worse outcomes including the primary endpoint and all-cause death than those with acute procedure success (APS) defined as residual MR 2+ (n=125) or 1+ (n=105). Among patient with APS, background characteristics including age, MR etiology, heart failure severity, and LV function were not different. Although MR grade and NT-pro BNP level at 6months after MC were higher in patients with residual MR 2+, there was no significant difference in the incidence of the primary endpoint and all-cause death. Subanalysis showed that the primary endpoint occurred more frequently in patients with MR 2+ in patients with LV ejection fraction ≤40%, chronic kidney disease, and baseline NYHA-class IV.


CONCLUSIONS
Procedure failure was associated with adverse outcomes after MC. Among patients with APS, residual MR 2+ was not significantly associated with overall worse outcomes than residual MR 1+. However, residual MR 2+ was associated with poorer prognosis in patients with impaired LV function, renal dysfunction, and severe heart failure, suggesting that the optimal endpoint of MC procedure should be individualized according to each patient's baseline characteristic.
Department of Cardiology, Heart Center Brandenburg, Germany; Department of Cardiology, Medical School Brandenburg, Germany.
Hidehiro
H
Kaneko
Department of Cardiology, Heart Center Brandenburg, Germany; Department of Cardiology, Medical School Brandenburg, Germany.
Michael
M
Neuss
Department of Cardiology, Heart Center Brandenburg, Germany; Department of Cardiology, Medical School Brandenburg, Germany.
Jens
J
Weissenborn
Department of Cardiology, Heart Center Brandenburg, Germany; Department of Cardiology, Medical School Brandenburg, Germany. Electronic address: c.butter@immanuel.de.
Christian
C
Butter
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006350:Heart Valve Prosthesis / Q000009:adverse effects / Q000639:trends*; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000639:trends*; D006801:Humans; D008297:Male; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000601:surgery*; D011183:Postoperative Complications / Q000000981:diagnostic imaging* / Q000209:etiology*; D012189:Retrospective Studies; D013525:Surgical Instruments / Q000009:adverse effects / Q000639:trends; D016896:Treatment Outcome
Chronic kidney disease; Heart failure; Left ventricular function; MitraClip; Residual mitral regurgitation