title: [The frequency of aspirin resistance by a modified thrombelastography method and its relationship with clinical and laboratory parameters in patients with stable coronary artery disease].
abstract: OBJECTIVE
  Aspirin is the cornerstone of antiplatelet therapy in cardiovascular medicine. However, aspirin resistance has been demonstrated in 0.4% to 83.3% of aspirin-receiving patients. The aim of this study was to investigate the frequency of aspirin resistance using a modified thrombelastography (mTEG) method and related clinical and biochemical parameters in patients with stable coronary artery disease (CAD), who received 100 mg/day aspirin.
  
  
  METHODS
  The study included 168 patients (115 males, 53 females; mean age 60±8 years) with stable CAD, receiving aspirin at a dose of 100 mg/day. Aspirin responsiveness was determined using mTEG, where aspirin resistance was defined as arachidonic acid-induced whole blood platelet aggregation inhibition (PAI) of less than 50%.
  
  
  RESULTS
  Aspirin resistance was detected in 27 patients (16.1%). Platelet aggregation inhibition showed negative correlations with hyperlipidemia, smoking, spironolactone use, systolic blood pressure, pulse pressure, and total cholesterol and fibrinogen levels. In multivariate regression analysis, only fibrinogen level (OR=1.063, p=0.010) and pulse pressure (OR=1.197, p=0.023) were found to be independent indicators of aspirin resistance and PAI. In ROC analysis, cut-off values of 50 mmHg for pulse pressure and 400 mg/dl for fibrinogen level predicted aspirin resistance with 88.9% and 74% sensitivity and 64.4% and 68% specificity, respectively.
  
  
  CONCLUSIONS
  Our findings suggest that measurements of fibrinogen level and pulse pressure may be used as easy and reliable methods in predicting aspirin resistance.
authors.affiliation: Department of Cardiology, Adana Numune Education and Research Hospital, Adana, Turkey. cardiology79@yahoo.com
authors.forename: Durmuş Yıldıray
authors.initials: DY
authors.lastname: Sahin
authors.forename: Mevlüt
authors.initials: M
authors.lastname: Koç
authors.forename: Murat
authors.initials: M
authors.lastname: Caylı
authors.forename: Onur Kadir
authors.initials: OK
authors.lastname: Uysal
authors.forename: Osman
authors.initials: O
authors.lastname: Karaarslan
authors.forename: Mehmet
authors.initials: M
authors.lastname: Kanadaşı
authors.forename: Mustafa
authors.initials: M
authors.lastname: Demirtaş
mesh_terms: D001241:Aspirin / Q000008:administration & dosage*; D003324:Coronary Artery Disease / Q000097:blood / Q000188:drug therapy*; D004334:Drug Administration Schedule; D004351:Drug Resistance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D011237:Predictive Value of Tests; D012372:ROC Curve; D012680:Sensitivity and Specificity; D013916:Thrombelastography
chemical_list: D010975:Platelet Aggregation Inhibitors; D001241:Aspirin