Elsevier

International Journal of Cardiology

Volume 345, 15 December 2021, Pages 29-35
International Journal of Cardiology

Clinical and echocardiographic outcomes of transcatheter mitral valve repair in atrial functional mitral regurgitation

https://doi.org/10.1016/j.ijcard.2021.09.056Get rights and content

Highlights

  • Only 4.5% of our cohort fulfilled criteria for AFMR

  • Patients with AFMR showed a significant functional improvement at 6- and 12-month follow-up in our series.

  • The probability of survival free of readmission for heart failure and all-cause mortality within the first year after TMVR was 74.9%.

  • Procedural and clinical outcomes, as well as recurrent rates of MR were similar acutely and at 1-year compared to other etiologies of MR

Abstract

Background

Isolated atrial fibrillation can cause mitral regurgitation (MR) in patients with normal left ventricular systolic function and no organic disease of the mitral valve. Little information is available regarding outcomes of Mitraclip in patients with atrial functional mitral regurgitation (AFMR). We aimed to evaluate 12-month clinical and echocardiographic outcomes of transcatheter mitral valve repair (TMVR) with MitraClip in patients with AFMR compared to those with ventricular functional or degenerative/mixed MR.

Methods

Registry-based analysis of all consecutive patients who underwent TMVR and were included in the Spanish Registry of Mitraclip. Changes in MR and NYHA functional class, and a combined endpoint including all-cause mortality and hospitalizations due to heart failure were the main outcomes.

Results

Overall, 1074 (69.1% male, 73.3 ± 10.2 years-old) patients were analyzed in this report. 48 patients (4.5%) presented AFMR. AFMR was significantly reduced after TMVR, with a procedural success rate of 91.7%, and this reduction persisted at 12-month (p < 0.001). Patients with AFMR showed a significant functional improvement at 6- and 12-month follow-up in our series (baseline: NYHA III 70.8% IV 18.8% vs. 1-year: NYHA III 21.7% IV 0%; p < 0.001). The probability of survival free of readmission for heart failure and all-cause mortality within the first year after TMVR was 74.9%. Procedural and clinical outcomes, as well as recurrent rates of MR were similar acutely and at 1-year compared to other etiologies.

Conclusion

TMVR in patients with AFMR showed no significant differences compared to ventricular functional or degenerative/mixed MR regarding MR reduction or clinical outcomes.

Introduction

Mitral regurgitation (MR) has been traditionally classified as primary or secondary depending on the etiology of the valvular disease [1]. Primary MR (PMR) is due to the organic disease of the mitral valve (MV) leaflets and myxomatous degeneration is the most common cause. On the contrary, secondary MR, also known as functional MR (FMR), is related to the dilatation of the MV annulus (MVA) and/or the dysfunction of the subvalvular apparatus in patients with normal MV leaflets. To date, FMR mainly referred to the restriction of the MV leaflets' movement caused by the remodeling of one or both papillary muscles in patients with ischemic heart disease (IHD) or dilated cardiomyopathy. Therefore, FMR is commonly used as a synonymous of left ventricular (LV) MV disease.

Nevertheless, in the last years, a new type of FMR has been described associated to the dilatation of the MVA in patients with preserved LV function and long-standing atrial fibrillation (AF) [2]. Despite the high prevalence and frequent coexistence of both, MR and AF, very little is known about prognosis and outcomes after different therapeutic strategies of the so-called atrial FMR (AFMR) [3]. Randomized trials and several registries have proved the safety and efficacy of MitraClip (Abbott Vascular, Santa Clara, CA) to reduce mitral insufficiency in patients with ventricular FMR. In this population, MitraClip has shown to reduce mortality and HF hospitalizations, and to improve functional class and quality of life on top of stand-alone medical therapy [4], [5]. However, the use of transcatheter edge-to-edge repair (TEER) in patients with AFMR is poorly studied. Our aim was to address clinical and echocardiographic outcomes in patients with AFMR undergoing transcatheter edge-to-edge mitral valve repair with MitraClip compared to those with ventricular FMR (VFMR), PMR or mixed MR (MMR).

Section snippets

Methods

The Spanish MitraClip multicenter registry prospectively included all consecutive patients with symptomatic grade 3+ or 4+ MR undergoing TEER from June 2012 in 24 participating Institutions. In this observational study we evaluated the data from 1124 patients enrolled until July 21, 2020. Cases in which key information for screening of AFMR was missing (n = 33, 3.0%) and those with history of failed prior annuloplasty (n = 17, 1.5%) were excluded (Fig. 1).

Fig. 1 shows the screening flow chart.

Results

Overall, 1074 were analyzed in this report (Fig. 1). Patients with organic MV disease were classified as PMR or MMR (n = 402, 37.4%) and the rest of them were grouped as FMR (n = 672, 62.6%). Among patients with FMR, 48 (4.5%) subjects met criteria for AFMR.

Table 1 shows the baseline characteristics of the included cohort grouped by MR etiology. Patients with AFMR were significantly older (p < 0.001), more frequently women (p < 0.001) and had a higher body mass index (p = 0.006), as well as a

Discussion

To the best of our knowledge, this is the first multicenter registry to address clinical and echocardiographic outcomes of AFMR after TEER in the real-world setting. The main findings of our study were the following: 1) the prevalence of “pure” AFMR was low in our series; 2) MVA dilatation was a constant finding in this population; 3) TMVR effectively reduced AFMR with similar recurrence rates at 12-month follow-up vs VFMR or PMR/MMR; 4) After TEER, patients with AFMR showed an improvement in

Statement

All authors take responsibility for all aspects of the reliability and freedom from bias of the data presented and their discussed interpretation.

Funding source

The website database and statistical analyses were supported by an unrestricted grant from Abbott Vascular.

Declaration of Competing Interest

Rodrigo Estevez-Loureiro is a consultant and proctor for Abbott Vascular. Dabit Arzamendi is a consultant and proctor for Abbott Vascular. Xavier Freixa is a consultant and proctor for Abbott Vascular. Luis Nombela-Franco is a consultant and proctor for Abbott Vascular. Garrote-Coloma is proctor for Abbott Vascular. Ignacio Cruz-González is proctor for Abbott Vascular. Juan Horacio Alonso-Briales is a consultant and proctor for Abbott Vascular. Isaac Pascual is proctor for Abbott Vascular. The

References (23)

Cited by (17)

  • Heart Failure and Secondary Mitral Regurgitation: A Contemporary Review

    2023, Journal of the Society for Cardiovascular Angiography and Interventions
  • Incidence and causal association of functional atrial mitral regurgitation in HFpEF

    2023, Hellenic Journal of Cardiology
    Citation Excerpt :

    Catheter-based intervention (MitraClip) theoretically may prove to be effective and a useful treatment choice, but it has to be proved by studies, which for the time being are limited and with small number of patients involved.42,43 Nevertheless, the results of these studies indicate that transcatheter MV repair is the interventional method of choice, especially in elderly patients.44,45,46 In summary, it seems that presently, the more appropriate noninterventional therapeutical approach for AFMR is prevention of LA dilatation and early treatment of AF.

View all citing articles on Scopus
View full text