The effect of high-dose aspirin pre-treatment on the incidence of myonecrosis following elective coronary stenting

Background Inadequate platelet response to aspirin is associated with increased incidence of peri-procedural myonecrosis. Antiplatelet activity of aspirin can be improved by increasing the dose. High-dose aspirin pre-treatment, therefore, may reduce the incidence of myonecrosis post stenting. Methods and results Two-hundred patients taking 75–325mg daily doses of aspirin for at least 2 weeks were randomized for addition or no addition of 500mg aspirin before elective coronary stenting (aspirin 500 group, n =100 and control group, n =100). Primary endpoint was the occurrence of peri-procedural myonecrosis defined as creatine kinase-myocardial band (CK-MB) elevation of >1× upper limits of normal (ULN). Aspirin 500 patients were significantly younger and more likely to have family history of coronary artery disease, but less likely to have received statins than controls. Elevation of CK-MB was observed in 29% of aspirin 500 patients and 15% of controls ( p =0.017). The incidence of non-Q wave myocardial infarction (CK-MB elevation of >3×ULN) tended to be higher in the aspirin 500 group than in the control group (5% versus 0%, p =0.059). Multivariate analysis identified baseline aspirin dose (OR: 1.006; 95% CI: 1.002–1.010; p =0.004), aspirin 500mg treatment (OR: 2.5; 95% CI: 1.2–5.5; p =0.021) and baseline CK-MB level (OR: 1.4; 95% CI: 1.1–1.7; p =0.012) as independent predictors of CK-MB elevation after coronary stenting. Conclusion For patients taking daily low-dose aspirin therapy, supplementation with high-dose aspirin before elective coronary stenting does not reduce, but may increase the incidence of peri-procedural myonecrosis.