Impact of Intraprocedural Mitral Regurgitation and Gradient Following Transcatheter Edge-to-Edge Repair for Primary Mitral Regurgitation

JACC Cardiovasc Interv. 2024 Jul 8;17(13):1559-1573. doi: 10.1016/j.jcin.2024.05.018.

Abstract

Background: The impact of intraprocedural results following transcatheter edge-to-edge repair (TEER) in primary mitral regurgitation (MR) is controversial.

Objectives: This study sought to investigate the prognostic impact of intraprocedural residual mitral regurgitation (rMR) and mean mitral valve gradient (MPG) in patients with primary MR undergoing TEER.

Methods: The PRIME-MR (Outcomes of Patients Treated With Mitral Transcatheter Edge-to-Edge Repair for Primary Mitral Regurgitation) registry included consecutive patients with primary MR undergoing TEER from 2008 to 2022 at 27 international sites. Clinical outcomes were assessed according to intraprocedural rMR and mean MPG. Patients were categorized according to rMR (optimal result: ≤1+, suboptimal result: ≥2+) and MPG (low gradient: ≤5 mm Hg, high gradient: > 5 mm Hg). The prognostic impact of rMR and MPG was evaluated in a Cox regression analysis. The primary endpoint was 2-year all-cause mortality or heart failure hospitalization.

Results: Intraprocedural rMR and mean MPG were available in 1,509 patients (median age = 82 years [Q1-Q3: 76.0-86.0 years], 55.1% male). Kaplan-Meier analysis according to rMR severity showed significant differences for the primary endpoint between rMR ≤1+ (29.1%), 2+ (41.7%), and ≥3+ (58.0%; P < 0.001), whereas there was no difference between patients with a low (32.4%) and high gradient (42.1%; P = 0.12). An optimal result/low gradient was achieved in most patients (n = 1,039). The worst outcomes were observed in patients with a suboptimal result/high gradient. After adjustment, rMR ≥2+ was independently linked to the primary endpoint (HR: 1.87; 95% CI: 1.32-2.65; P < 0.001), whereas MPG >5 mm Hg was not (HR: 0.78; 95% CI: 0.47-1.31; P = 0.35).

Conclusions: Intraprocedural rMR but not MPG independently predicted clinical outcomes following TEER for primary MR. When performing TEER in primary MR, optimal MR reduction seems to outweigh the impact of high transvalvular gradients.

Keywords: mitral valve; primary mitral regurgitation; residual mitral regurgitation; transcatheter edge-to-edge repair.

Publication types

  • Multicenter Study
  • Observational Study

MeSH terms

  • Aged
  • Aged, 80 and over
  • Cardiac Catheterization* / adverse effects
  • Cardiac Catheterization* / instrumentation
  • Cardiac Catheterization* / mortality
  • Female
  • Heart Failure / diagnostic imaging
  • Heart Failure / etiology
  • Heart Failure / mortality
  • Heart Failure / physiopathology
  • Heart Failure / therapy
  • Heart Valve Prosthesis Implantation* / adverse effects
  • Heart Valve Prosthesis Implantation* / instrumentation
  • Heart Valve Prosthesis Implantation* / mortality
  • Hemodynamics*
  • Humans
  • Male
  • Mitral Valve Insufficiency* / diagnostic imaging
  • Mitral Valve Insufficiency* / mortality
  • Mitral Valve Insufficiency* / physiopathology
  • Mitral Valve Insufficiency* / surgery
  • Mitral Valve* / diagnostic imaging
  • Mitral Valve* / physiopathology
  • Mitral Valve* / surgery
  • Recovery of Function*
  • Registries*
  • Risk Assessment
  • Risk Factors
  • Time Factors
  • Treatment Outcome