MitraClip device for patients with functional mitral valve regurgitation: A systematic review

Percutaneous Mitral Valve Repair for Secondary Mitral Regurgitation: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to investigate whether percutaneous mitral valve repair (PMVr) using MitraClip was more effective than surgery or medical therapy for long-term morbidity and mortality. We searched MEDLINE, EMBASE, and CENTRAL (Cochrane Library) databases to identify relevant studies that recruited adult patients with functional or secondary mitral valve regurgitation who underwent PMVr with MitraClip implantation using appropriate search terms and Boolean operators. The odds ratios (ORs) were pooled using the random-effects model. A total of 14 studies recruiting 2,593 patients were included. Within 12 months of follow-up, patients who underwent PMVr did not maintain mitral valve regurgitation grade 2+ (OR 0.22, 95% confidence interval [CI] 0.12 to 0.41, p <0.0001, I2 = 0.0%, p = 0.52) or symptom-free heart failure (OR 0.47, 95% CI 0.29 to 0.77, p = 0.0028, I2 = 0.0%, p = 0.66) compared with their surgical counterparts. Patients were more likely to be rehospitalized for heart failure (OR 2.79, 95% CI 1.54 to 5.05, p = 0.0007, I2 = 0.0%, p = 0.51). However, there was no difference between the groups in terms of all-cause or cardiovascular mortality. Whereas, in comparison with medical therapy, PMVr significantly reduced all-cause mortality at 12 and ≥24 months of follow-up (OR 0.41, 95% CI 0.24, 0.69, p = 0.0009, I2 = 32%, p = 0.23 and OR 0.55, 95% CI 0.40, 0.75, p = 0.0002, I2 = 0.0%, p = 0.45, respectively). In conclusion, there was no difference in all-cause death at 12 or 24 months of follow-up between PMVr and the surgical approach, but the durability of valvular repair was inferior with PMVr. In comparison with medical therapy, there was a significant reduction in mortality with PMVr.

Percutaneous Interventions for Secondary Mitral Regurgitation

Mitral regurgitation is frequently associated with ventricular dysfunction and carries a high mortality. Guideline-directed medical therapy, surgical mitral valve repair or replacement, and, in the setting of advanced heart failure, heart transplant and left ventricular assist devices have been the mainstay of treatment. However, rapid advancement in the field has resulted in approval of edge-to-edge mitral valve repair with the MitraClip, and there are several novel catheter-based percutaneous options in clinical trials. Percutaneous options, while promising, must be deployed in patients who are most likely to benefit, and thus, understanding the pathophysiology of specific subgroups of patients with functional mitral regurgitation (eg, disproportionate versus proportionate mitral regurgitation) is key to the success of new devices. We review the pathophysiology, percutaneous therapeutic treatment options, and ongoing clinical trials for functional mitral regurgitation.

MitraClip and left ventricular reverse remodelling: a strain imaging study

AIMS

The purpose of this study is to identify echocardiography predictors of clinical response and reverse left ventricular (LV) remodelling in patients with functional mitral regurgitation (FMR) treated with MitraClip.

METHOD AND RESULTS

We retrospectively analysed 86 high surgical risk patients with severe FMR; of those, 58 were implanted a MitraClip, and 28 received medical treatment and served as controls. At baseline and at 1-year follow-up, we performed clinical and echocardiography evaluation to assess global longitudinal strain (GLS) and myocardial work [global work index (GWI), global constructive work (GCW), global wasted work (GWW), global work efficiency (GWE)]. Mitral regurgitation was significantly reduced after MitraClip implantation (3.7 ± 0.4 vs. 1.7 ± 0.8, P < 0.001), and the procedure was associated with improvement in brain natriuretic peptide levels (980 ± 1027 vs. 420 ± 338 pg/mL, P < 0.001), New York Heart Association class status (3.2 ± 0.55 vs. 2.0 ± 0.6, P < 0.001), 6-min walking test (233 ± 154 vs. 286 ± 114 m, P = 0.01) at follow-up and reduction of left ventricle end-systolic (LVESV) and left ventricle end-diastolic volumes (LVEDV) (152 ± 68 vs. 136 ± 43 mL, P = 0.004 & 219 ± 74 vs. 193 ± 66 mL, P = 0.001, respectively). MitraClip procedure was associated with improvement of LV performance and significant increase of GWI (607 ± 282 vs. 650 ± 260 mmHg%, P = 0.045) and GCW (854 ± 288 vs. 949 ± 325 mmHg%, P < 0.001). Baseline ejection fraction (EF), GLS, GWI, GCW, and effective regurgitant orifice area were the variables that were associated with reduction of LVEDV 1 year after intervention (P < 0.05 for all) and baseline GCW of the LV was the only variable associated with reduction of LVESV (P = 0.002). Receiver operating characteristic curve analysis identified that a GLS cut-off value of -8.65% (AUC 0.815, P = 0.007) was associated with a 20% reduction of the LVEDV with a sensitivity and specificity of 72% and 70%, respectively, and that a GCW cut-off value of 846 mmHg% (AUC 0.759, P = 0.007) was associated with a 10% reduction of LVESV with sensitivity and specificity 79% and 74%, respectively.

CONCLUSIONS

Mitral valve repair with MitraClip has positive clinical and echocardiographic impact in patients with FMR 1 year after implantation. Preserved GLS and GCW values appear to be associated with LV reverse remodelling post intervention.

Transcatheter management of valvular regurgitation beyond the aortic valve (mitral - tricuspid valve): Literature overview and future perspectives

The growth of the available transcatheter treatment approaches for the mitral and tricuspid position was accompanied by important clinical trials and studies through the last years. The selection of appropriate candidates for transcatheter techniques requires significant insight into anatomical limitations of each patient undergoing clinical evaluation. Furthermore, technological characteristics of the available devices, and risks and benefits of each potential therapy, play the most important role in a physician's decision. This knowledge should be valuable to both interventional cardiologists and researchers. This paper aims to offer a concise overview of the technological advances in this field of Interventional Cardiology. Trials and studies announced at the major interventional cardiology congresses during 2018 and 2019 were systematically reviewed. Moreover, a literature search in PubMed for the same period identified an amount of publications eligible for inclusion, based on their relevance to the subject, and their potential impact on current guidelines of good clinical practice.

Stroke after transcatheter edge-to-edge mitral valve repair: a systematic review and meta-analysis

AIMS

The aim of this study was to assess the stroke rate after transcatheter mitral valve repair (TMVR) with the MitraClip, comparing it with surgical mitral valve repair (SMVR) and optimal medical treatment (OMT).

METHODS AND RESULTS

In December 2018, we systematically searched PubMed, Embase and Cochrane Controlled Register of Trials for studies comparing TMVR with SMVR and/or OMT for the treatment of severe mitral regurgitation. Random-effects and cumulative meta-analysis was performed. Ten studies were included (seven of TMVR versus SMVR and three of TMVR versus OMT), providing a total of 1,881 patients and 61 pooled strokes (16 in TMVR versus SMVR and 45 in TMVR versus OMT). There was no difference in stroke incidence between TMVR and SMVR (pooled OR 0.49 [0.17, 1.42], p=0.19). However, there was a trend towards a lower stroke risk in TMVR. For TMVR versus OMT, no difference in stroke rate was identified (pooled OR 1.09 [0.60, 1.97], p=0.79). Post-procedure de novo atrial fibrillation was more frequent in SMVR when compared with TMVR.

CONCLUSIONS

Despite both a low number of pooled stroke events and the failure to reach the pre-specified statistical significance, there was a trend for a lower post-procedure stroke rate in TMVR when compared with SMVR and a similar one between TMVR and OMT alone.