Myocardial Injury After Transcatheter Mitral Valve Replacement Versus Surgical Reoperation

Area of Science:

• Cardiology
• Cardiovascular Surgery
• Interventional Cardiology

Background:

• Mitral bioprosthesis dysfunction requires intervention, with transcatheter mitral valve replacement (TMVR) and surgical mitral valve replacement reoperation (SMVR-REDO) as options.
• Assessing myocardial injury and its clinical implications post-intervention is crucial for patient outcomes.

Purpose of the Study:

• To compare the incidence and clinical impact of myocardial injury, indicated by cardiac biomarker elevation, between TMVR and SMVR-REDO.
• To identify predictors of mortality following these procedures.

Main Methods:

• A cohort study included 310 patients with mitral bioprosthesis failure (90 TMVR, 220 SMVR-REDO) from 2014-2023.
• Cardiac biomarkers (CK-MB, cTn) were measured serially post-intervention.
• Multivariable analysis and propensity score matching adjusted for baseline differences; outcomes assessed per MVARC criteria.

Main Results:

• Nearly all patients experienced biomarker increases post-intervention (100% SMVR-REDO vs. 94% TMVR), peaking at 6-12 hours.
• SMVR-REDO showed a 2-3 fold higher increase in cardiac biomarkers compared to TMVR.
• Thirty-day mortality was 16.8% (SMVR-REDO) vs. 13.3% (TMVR); at 19 months, it was 17.7% (SMVR-REDO) vs. 21.1% (TMVR).

Conclusions:

• Myocardial injury is a systemic event following mitral bioprosthetic degeneration treatment, particularly after SMVR.
• Elevated CK-MB and cTn levels are associated with increased cumulative late mortality, irrespective of the treatment approach.