Contemporary Practice Patterns and Outcomes for Patients With Mitral Regurgitation: Results From a Large Multicenter Real-World Database

BACKGROUND

• Guidelines for management of mitral regurgitation (MR) recommend grading the severity of disease using echocardiographic criteria^1,2
• Current guidelines specify that for select patients with severe MR, procedural (surgical or transcatheter) intervention is recommended¹
• Contemporary data on rates of procedural intervention and corresponding untreated mortality for patients across all degrees of MR severity are lacking

METHODS

• De-identified real-world dataset (January 2018 to May 2023) of 1,177,381 patients from 25 US institutions participating in the egnite Database (egnite, Inc., Aliso Viejo, CA, USA) with appropriate permissions
• Given the dynamic nature of MR (particularly secondary/functional MR), the dataset treated MR as a time-varying covariate, with index event for study entry being first MR diagnosis
• Key outcomes: 2-year rates of treatment with mitral valve (MV) intervention and mortality without intervention were assessed using Kaplan-Meier estimates (results compared via log-rank test)
• Associations between individual covariates of interest and mortality without intervention were also assessed in a Cox model with all covariates treated as time-varying

RESULTS

• Of the 1,177,381 patients total, 936,993 patients had documented MR diagnosis with specified severity and were included in the main study analyses
• Median (interquartile range) time from index to death, MV intervention, or last documented clinical encounter was 448 (120-887) days
• Rates of intervention at 2 years were relatively low for patients with moderate-to-severe or severe MR
• At 2 years, estimated intervention rates (95% confidence interval [CI]) were:
  • 13.5% (12.6%-14.5%) for moderate-to-severe MR
  • 46.4% (44.9%-47.9%) for severe MR

• Mortality without MV intervention increased with greater MR severity
• At 2 years, estimated mortality rates (95% CI) were:
  • 30.2% (29.0%-31.4%) for moderate-to-severe MR
  • 31.8% (30.3%-33.4%) for severe MR

• Greater MR severity was independently associated with greater untreated mortality

CONCLUSIONS

• Despite untreated MR being associated with increased mortality, intervention rates for these patients remain relatively low
• Untreated mortality increased incrementally with greater MR severity and the presence of symptoms
• Further study is needed to assess optimal timing of procedural intervention for these patients