Antiplatelet therapy and long-term mortality in patients with myocardial injury after non-cardiac surgery

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.