Increasing the dosage of aspirin before percutaneaous coronary intervention: is there any effect in aspirin resistant patients? A randomized study

Abstract number: P0242

Hézard^* N., Metz† D., Droull醠C., Nazeyrollas† P., Potron† G., Nguyen† P.

†France ^*Laboratoire Central d'Hématologie, France;

Background  

In the setting of percutaneous coronary angioplasty (PCI), aspirin is the main treatment strategy to reduce the incidence of procedural adverse ischemic events. Moreover, the efficiency of acetylsalicylic acid (ASA) is largely debated, with the current concept of good and poor responders. The aim of the study was to determine whether a 500-mg aspirin bolus given just before PCI could be beneficial in terms of platelet inhibition, especially in the focus of preliminary aspirin resistance.

Patients and methods  

Fifty patients under 160 mg aspirin daily regimen were randomized to receive the bolus before PCI (n = 25). Ticlopidin was given at a 500-mg loading dose in the case of stent implantation. PFA-100 closure times (CT) were implemented using the collagen-epinephrin cartridge (CEPI) in citrated whole blood, drawn before and 2 h after PCI. Aspirin resistance was defined as normal CEPI CT despite aspirin treatment (<165 s). Intra-individual comparisons were tested using Wilcoxon's matched-pairs signed rank test. Comparison between groups was performed using the Mann–Withney–Wilcoxon test. A value of P < 0.05 was regarded as significant.

Results  

Twenty-six patients (52%) were classified as poor responders before angioplasty. In this group of patients, 14 received the IV bolus. Among them, 12 (85%) kept normal CEPI CT. Results are reported in the table below as median [interquartiles].

Conclusion  

We report here (1) a high proportion of patients presenting a lack of ASA sensitivity, including oral and IV ASA regimen, and (2) no particular advantage of an additional ASA bolus in the subset of patients described as poor responders to chronic aspirin regimen.

Table 1