Transcatheter edge to edge repair using the ease-of-use valve clamp system for functional mitral regurgitation: a primary report

Outcomes of transcatheter edge-to-edge repair for atrial functional mitral regurgitation: A meta-analysis of observational studies

BACKGROUND

Transcatheter edge-to-edge repair (TEER) may have potential benefits in the treatment of atrial functional mitral regurgitation (AFMR), but robust evidence is currently lacking. We conducted a systematic review and meta-analysis to investigate the clinical outcomes of TEER for AFMR, including comparisons to ventricular functional MR (VFMR).

METHODS

MEDLINE and EMBASE were searched through January 2023 to identify studies eligible for analysis. The primary outcome was postprocedural MR severity. Postprocedural New York Heart Association (NYHA) functional class classification and all-cause mortality were also evaluated. Outcomes were stratified into short term (postprocedure to 6 months) and long term (6 months to 2 years).

RESULTS

A total of eight observational studies met the inclusion criteria, enrolling 539 AFMR and 3486 VFMR patients. Postprocedural MR grade ≤2 in the AFMR group was observed in 93.7% (454/491 patients; 95% confidence interval (CI), 91.1%-96.2%, I2  = 24.3%) and 97.1% (89/93 patients; 95% CI, 92.9%-100%, I2  = 26.4%) in short- and long-term follow-up, respectively. There was no difference in the rates of postprocedural MR grade ≤2 between AFMR and VFMR either in short-term (risk ratio [RR], 1.00 [95% CI, 0.95-1.06]; p = 0.90; I2  = 53%) or long-term follow-up (RR, 1.08 [95% CI, 0.89-1.32]; p = 0.44; I2  = 22%). Similarly, no difference was observed between AFMR and VFMR in the rates of postprocedural NYHA class ≤2 or all-cause mortality.

CONCLUSION

TEER provides similar clinical outcomes for AFMR and VFMR. A high rate of MR grade ≤2 was observed in patients at both short- and long-term follow-ups. Further prospective studies with TEER versus medical therapy and/or rhythm control for AFMR are warranted.

A case report of transcatheter repair of severe functional mitral regurgitation in cardiac amyloidosis

Background

Transcatheter therapy has become an alternative for functional mitral regurgitation (FMR) in patients at high surgical risk. However, the intervention of FMR in cardiac amyloidosis (CA) with transcatheter edge-to-edge repair (TEER) is controversial due to the potential risk of left atrial pressure (LAP) elevation.

Case summary

An 83-year-old woman with repeated heart failure (HF) and severe mitral regurgitation (MR) was referred to our centre for TEER. Pre-procedural transthoracic echocardiography (TTE) and transoesophageal echocardiography (TOE) confirmed the degree of MR and a functional aetiology. A peculiar LAP increase in this patient occurred immediately after successful TEER clip implantation and her n-terminal prohormone of brain natriuretic peptide significantly increased post-operatively. The diagnosis of CA was suspected and was subsequently established through endomyocardial biopsy. Aggressive anti-HF therapy was initiated and the patient was discharged after her HF symptoms were relieved. At 6-month follow-up, the patient was still alive and no episode of acute HF was experienced.

Discussion

Severe functional MR in CA treated with TEER has the potential risk of increasing LAP. During the short-term follow-up, TEER appears beneficial for left heart function (reduction of MR) but harmful for right heart function (increase of LAP). CA patients with severe FMR should be carefully evaluated about the benefits and potential harm of TEER intervention.