Abstract 1713: Aspirin-insensitive Thromboxane Synthesis Predicts Future Cardiovascular Events In Patients With Stable Coronary Artery Disease
The presence of urinary 11-dehydrothromboxane B2 (11-d-TXB2), a stable metabolite of thromboxane A2 is believed to be predominantly attributable to platelet activation and should decrease after aspirin treatment. Little is known about clinical outcome and aspirin-insensitive thromboxane synthesis in patients with stable coronary artery disease .The aim of this study is to clarify relationship between urinary levels of 11-d-TXB2 and the cardiovascular events in patients with stable coronary artery disease. We prospectively studied 82 consecutive patients with stable coronary artery disease. Patients were followed-up clinically for the occurrence of cardiovascular events, a composite of myocardial infarction, percutaneous coronary intervention, coronary artery bypass graft, ischemic stroke, and death. All patients had received daily aspirin therapy (100mg daily) for at least 1 month. Urinary levels of 11-d-TXB2 were also evaluated. Mean follow up periods were 1195 ± 300 days. A total of 12 (14.6%) patients experienced the end point event. In multivariate regression analysis, the 11-d-TXB2 levels were significantly associated with the occurrence of the composite cardiovascular event (P = 0.03). This association was independent of traditional cardiovascular risk factors. According to receiver operating characteristic (ROC) curves, cardiovascular events were best predicted by 11-d-TXB2. When using the cut-off levels derived from ROC, high levels of 11-d-TXB2 ( > 25.1 ng/mmol • Creatinine) were associated with increased risk of future cardiovascular events. Aspirin-insensitive thromboxane synthesis predicts future cardiovascular events in patients with stable coronary artery disease. Routine measurement of 11-d-TXB2 levels might be a useful tool for identifying high-risk patients in order to plan aggressive diagnostic protocols and prevention therapies.