An Updated Meta-Analysis of Treatment in Patients with Heart Failure Complicated Ventricular Functional Mitral Regurgitation

TL;DR

This study compares treatments for heart failure with functional mitral regurgitation, finding that surgical mitral valve repair improves heart function but not survival, while MitraClip reduces mortality.

Contribution

A meta-analysis comparing surgical and transcatheter treatments for ventricular functional mitral regurgitation in heart failure patients.

Findings

Surgical mitral valve repair improved left ventricular ejection fraction compared to replacement.

Transcatheter MitraClip treatment was linked to reduced all-cause mortality.

MitraClip also improved left ventricular end-diastolic volume.

Abstract

Ventricular functional mitral regurgitation (FMR) is a
common morbidity in patients with heart failure (HF). In addition to
guideline-directed medical therapy, mitral valve (MV) repair or replacement has
become an option for such patients. However, the impact of different treatments
on cardiac remodeling, function, and clinical outcomes remains unclear.

We systematically searched PubMed, EMBASE, Medline, Clinical
Trials.gov, and the Cochrane Central Register of Controlled Trials with search
terms related to mitral regurgitation, mitral valve repair, surgical mitral valve
replacement, mitral annuloplasty device, and MitraClip. The outcomes were left ventricular
ejection fraction (LVEF), left ventricular (LV) remodeling, all-cause
mortality, cardiovascular death, and HF hospitalization. Sensitivity analysis was
performed by removing high-bias risk studies. The analysis was done by Review
Manager 5.4 Analyzer and MedCalc Statistical Software version 19.2.6.

This meta-analysis included 10 studies with a total of 2533
patients (567 with transcatheter MitraClip, 823 with surgical MV repair, 651 with
surgical MV replacement, and 492 with medical therapy). Our meta-analysis
revealed that surgical MV repair had significant improvement in LVEF compared to
the surgical MV replacement (mean differences (MD) 2.32, [95% CI 0.39, 4.25]),
while transcatheter MitraClip treatment was associated with LVEF reduction (MD
–4.82, [95% CI –7.29, –2.34]). In terms of LV remodeling, transcatheter
MitraClip treatment was associated with improvement in left ventricular
end-diastolic volume (MD –10.36, [95% CI –18.74, –1.99]). Furthermore,
compared to surgical MV replacement, surgical MV repair was not associated with a
reduction of all-cause mortality (risk ratio (RR) 0.83, [95% CI 0.61, 1.13]) and
cardiovascular death (RR 0.95, [95% CI 0.56, 1.62]), while transcatheter
MitraClip was associated with reduced risk of all-cause mortality (RR 0.87, [95%
CI 0.78, 0.98]).

Surgical MV repair was associated with
significant improvement in LVEF but had no significant effect on all-cause
mortality compared to surgical MV replacement. Transcatheter MitraClip was
associated with better long-term survival than the non-MitraClip group, thus,
transcatheter MitraClip could be considered an alternative treatment in patients
with HF-complicated ventricular FMR.

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