Predicting Bleeding Risk by Platelet Function Testing in Patients Undergoing Heart Surgery

Background: Predicting bleeding events in patients with coronary artery bypass grafting (CABG) represents an unmet medical need that may improve CABG outcomes. Hypotesis: To assess the potential link between platelet function testing and bleeding risk in patients undergoing CABG. Methods: Platelet aggregation and clinical outcomes in 478 patients treated with aspirin and/ or clopidogrel were retrospectively analyzed. Platelet activity was assessed prior to CABG with arachidonic acid (ASPI Test), and adenosine diphosphate(ADP Test) utilizing multiple-electrode aggregometry. Results: In the study group of 478 patients, mean age was 65.2 +/- 15.2 years; 138 were women. The majority of patients (n= 198) underwent on-pump surgery, with 162 undergoing off-pump and 30 undergoing minimally invasive surgery. Forty-eight patients received artificial valve implantation alone, and 40 received valve implantation in combination with CABG. The analysis of the entire pool revealed that an ASPI test value < 407 area under curve per minute (AUC*min) may be useful in predicting postoperative drainage. In CABG patients only, an ASPI test value < 271 AUC*min predicted the need for red blood cell concentrate transfusion following surgery. In patients who stopped clopidogrel for up to 5 days before surgery, the ADP test failed to exhibit prognostic utility for predicting bleeding risk. Conclusions: In patients undergoing heart surgery, an ASPI test value < 407 AUC*min may predict higher postoperative drainage, whereas < 271 AUC*min may be linked to postoperative use of red blood cell concentrate.