Impaired anti-platelet effect of aspirin, inflammation and platelet turnover in cardiac surgery☆☆☆

Abstract

A reduced platelet inhibitory response to acetyl salicylic acid (ASA) has been associated with an increased risk of graft thrombotic occlusion after coronary artery bypass grafting (CABG). We performed a prospective, observational study of 18 patients on 100 mg/day ASA before and after CABG. We assessed antiplatelet response to ASA and its relationship with platelet turnover, inflammatory markers, and soluble thrombomodulin (sTM) levels. All patients showed optimal response to ASA preoperatively but had higher values during follow-up. Platelet aggregation and platelet count in the perioperative period were significantly associated (P=0.05). Platelet turnover was defined as the average daily turnover (ADTO). The lowest inhibitory value (28% of patients > or =6 Omega) was recorded at the same time of the highest platelet turnover (>10% daily in 77.77% of patients), one week after CABG. ADTO >10% was associated with an increased risk of platelet aggregation > or =6 Omega. Levels of sTM were significantly higher one week after CABG (median 13 vs. 3 ng/ml preoperatively, P=0.0011). There is a transient impairment in ASA antiplatelet effect after CABG related to an increased platelet turnover caused by the inflammatory process. This could be responsible for the high risk of occlusive thrombosis.

The Prevalence and Clinical Relevance of ASA Nonresponse After Cardiac Surgery: A Prospective Bicentric Study

“…Arazi et al identified a significant correlation between this condition and a postoperative ASA nonresponse. 16 Assuming that a longer extracorporeal circulation leads to greater impairment of platelet function, one could suppose that the identification of the CPB time as an independent risk factor for an ASA nonresponse in the present study reflects a higher platelet turnover in patients with a longer CPB time. Because no laboratory markers for an increased platelet turnover were measured in this study, this question cannot be answered by the current results.…”

Fractions of aqueous and methanolic extracts from tomato (Solanum lycopersicum L.) present platelet antiaggregant activity

“…When collagen was used as agonist, inhibition was lower, whereas when arachidonic acid and thrombin receptor activator peptide were used, tomato showed no inhibitory effect [24]. These results rule out the platelet antiaggregant activity of salicylic acid or a related species [25].…”

Thrombomodulin and the vascular endothelium: insights into functional, regulatory, and therapeutic aspects

“…Consistent with this notion, elevated plasma TM levels have been found to correlate with atherosclerosis (119,158), cardioembolic stroke (38), obesity (165), Lupus erythomatosus-associated metabolic syndrome (105), preeclampsia (130), sepsis-associated disseminated intravascular coagulation (DIC) (90), and severe acute respiratory syndrome (SARS) (91). Significantly elevated plasma TM levels have also been observed in patients following coronary artery bypass graft (CABG) surgery (10,78). By contrast, several clinical studies report on vascular pathologies manifesting reduced sTM levels.…”