Abstract
BACKGROUNDS: Myocardial injury after non-cardiac surgery (MINS) has recently been accepted as a common complication associated with increased mortality. However, little is known about the treatment of MINS. The aim of this study was to investigate an association between antiplatelet therapy and long-term mortality after MINS. METHODS: From 2010 to 2019, patients with MINS, defined as having a peak high-sensitivity troponin I higher than 40 ng/L within 30 days after non-cardiac surgery, were screened at a tertiary centre. Patients were excluded if they had a history of coronary revascularisation before or during index hospitalisation. Clinical outcomes at 1 year were compared between patients with and without antiplatelet therapy at hospital discharge. The primary outcome was death, and the secondary outcome was major bleeding. RESULTS: Of the 3818 eligible patients with MINS, 940 (24.6%) received antiplatelet therapy at hospital discharge. Patients with antiplatelet therapy had a significantly lower mortality at 1 year than those without antiplatelet therapy (7.5% vs 15.9%, adjusted HR 0.60, 95% CI 0.45 to 0.79, p<0.001). A risk of major bleeding at 1 year was not significantly different between the patients with and without antiplatelet therapy (6.6% vs 7.6%, adjusted HR 0.85, 95% CI 0.62 to 1.17, p=0.324). In propensity score-matched analysis of 886 pairs, patients with antiplatelet therapy had a significantly lower risk of 1-year mortality (adjusted HR 0.53, 95% CI 0.39 to 0.73, p<0.001) than those without antiplatelet therapy. CONCLUSIONS: In patients with MINS, antiplatelet therapy at discharge was associated with decreased 1-year mortality.