Concomitant Tricuspid Repair in Patients with Degenerative Mitral Regurgitation

  • James S. Gammie Michael W.A. Chu Volkmar Falk Jessica R. Overbey Alan J. Moskowitz Marc Gillinov Michael J. Mack Pierre Voisine Markus Krane Babatunde Yerokun Michael E. Bowdish Lenard Conradi and the CTSN Investigators
  • N Engl J Med 2022;386:327-39

What was known?

Tricuspid regurgitation is commonly seen in patients with severe degenerative mitral regurgitation; however, it is not known whether performing tricuspid valve repair during mitral valve surgery will improve outcomes in patients with moderate tricuspid regurgitation or less-than-moderate regurgitation with annular dilatation. Clinical practice, therefore, varies widely, with concomitant tricuspid-valve repair and mitral-valve surgery occurring in 5–75% of patients.

Objective(s):

The aim of this study was to assess the benefits and risks of tricuspid-valve repair during mitral-valve surgery in patients with moderate or less-than-moderate tricuspid regurgitation who were undergoing surgery for degenerative mitral regurgitation.

What this study adds:

This study has provided valuable data to inform treatment decisions in a patient group whose optimal management has been the subject of controversy and wide variations in clinical practice.

Clinical implications:

These data suggest that, in the short term, tricuspid repair during mitral valve surgery is an appropriate strategy in patients with moderate tricuspid regurgitation.

Study design:

This randomised controlled trial (NCT02675244) was conducted at 39 clinical centres in the United States, Canada, and Germany. Patients were randomly assigned to undergo mitral valve surgery (n=203) alone or surgery with concomitant tricuspid annuloplasty (TA; n=198) using standard surgical techniques. Endpoints were assessed at 30 days and at 6, 12, 18, and 24 months. Survival was to be evaluated subsequently each year up to 60 months.

Primary endpoint:

  • Composite of reoperation for tricuspid regurgitation, progression of tricuspid regurgitation from baseline by two grades or the presence of severe tricuspid regurgitation, or death

Secondary endpoints:

  • Death
  • major adverse cardiac and cerebrovascular events (MACCE; a composite of death, stroke, or serious heart-failure)
  • Permanent pacemaker implantation
  • Length of hospital stay
  • Residual tricuspid regurgitation
  • Echocardiographic assessment of right ventricular size and functions

Inclusion criteria:

  • Adults undergoing mitral valve surgery for degenerative mitral regurgitation with either moderate tricuspid regurgitation or less-than-moderate regurgitation with annular dilatation of ≥ 40 mm (or 21mm/m2).

Notable exclusion criteria:

  • Secondary mitral regurgitation
  • Primary tricuspid valve disease
  • Suboptimal volume management

Findings:

  • Of the 401 participants, fewer primary end points were reported in those undergoing mitral valve surgery plus tricuspid annuloplasty (TA) than in those who underwent mitral valve surgery alone (3.9% vs. 10.2%) (relative risk [RR] 0.37; 95% confidence interval [CI], 0.16–0.86; p=0.02)
  • At 2 years, mortality was 3.2% and 4.5% in the surgery plus TA and surgery-alone groups respectively  (RR, 0.69; 95% CI, 0.25–1.88)
  • At 2 years, there was less progression of tricuspid regurgitation in the surgery plus TA group than in the surgery-alone group (0.6% vs. 6.1%; RR, 0.09; 95% CI, 0.01–0.69)
  • Similar frequencies of MACCE, functional status, and quality of life were reported in the two groups at 2 years
  • There was a higher incidence of permanent pacemaker implantation in the surgery-plus-TA group than in the surgery-alone group (14.1% vs. 2.5%; rate ratio, 5.75; 95% CI, 2.27–14.60)

Interpretation:

In patients with moderate or less-than-moderate tricuspid regurgitation, concomitant TA and mitral-valve surgery for degenerative mitral regurgitation has a significantly lower 2-year incidence of the composite end point. This difference was driven by a substantially lower incidence of progression of tricuspid regurgitation among patients who received TA. The use of TA did not affect the risk of death or other adverse outcomes. Tricuspid repair resulted in more frequent permanent pacemaker implantation; further study is warranted to investigate this finding. Longer follow-up is ongoing to fully determine the long-term clinical benefit.

Limitations:

  • The target of recruiting a sufficiently ethnically and racially diverse patient population was not achieved
  • Progression of tricuspid regurgitation was assessed by observational evidence only
  • The trial was not powered to draw inferences about the patients with either moderate tricuspid regurgitation or less-than-moderate regurgitation with annular dilatation individually
  • 24 months was insufficient follow-up to assess the long-term impact of progression of tricuspid regurgitation or permanent pacemaker implantation. The trial will continue over 5 years