Medical Student University of British Columbia - Vancouver, BC Vancouver, British Columbia, Canada
Background: Acute mitral regurgitation (MR) following myocardial infarction (MI) is a rare but life-threatening complication that arises from either papillary muscle rupture or dysfunction (primary MR) or post-infarct left ventricular remodeling (secondary MR). Surgical repair or replacement is often associated with high perioperative risk, leading to increased interest in transcatheter mitral valve interventions such as Mitral Transcatheter Edge-to-Edge Repair (M-TEER).
METHODS AND RESULTS: A systematic review was conducted following PRISMA 2020 guidelines. MEDLINE and EMBASE were searched to April 2025. Studies were eligible if they included adult patients undergoing M-TEER for MR within 90 days of MI and reported relevant clinical outcomes.
Eight studies were included (n = 1148 patients), including seven retrospective cohort studies. Procedural success rates for M-TEER were high (86.6%–100%) across both primary and secondary MR. There were no significant differences in procedural success amongst high risk groups, including those with cardiogenic shock (90% shock vs. 93% no shock, p = 0.793) and left ventricular ejection fraction (LVEF) < 35% (93.6% LVEF < 35% vs. 89.7% LVEF ≥35% p = 0.73). Complications, including partial clip detachment, cerebrovascular events, major bleeding events, or sepsis, ranged from 0-9% of cases across studies and were significantly lower than surgery in one comparative study (6% M-TEER vs. 34% surgery, p < 0.01). Mortality varied by MR type: across all studies, patients with secondary MR had lower in-hospital (6–14.4%) mortality compared to primary MR (30%). Compared to surgery, M-TEER had significantly lower in-hospital (6% M-TEER vs. 16% surgical, p = 0.03) and 1-year (17% M-TEER vs. 31% surgical, p = 0.04) mortality. Functional outcomes improved consistently, with most patients showing ≥1 NYHA class improvement post-M-TEER. MR grade was reduced to ≤2+ in 84–100% of cases at discharge across included studies.
Conclusion: M-TEER is a feasible and generally safe intervention for select patients with acute MR following MI, offering high procedural success and favorable short- and medium-term outcomes compared to surgery. It appears particularly beneficial in secondary MR and high-risk surgical candidates. However, outcomes remain less optimal in primary MR due to papillary muscle rupture/dysfunction, where surgery may still be necessary.
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