Abstract
Aortic stenosis (AS) and coronary artery disease (CAD) influence the coagulation system, potentially affecting hemostasis during cardiac surgery. Our aim was to evaluate 2 preoperative global hemostasis assays, plasma thrombin potential and thromboelastometry, in patients with severe aortic valve stenosis compared to patients with CAD. A secondary aim was to test whether the assays were associated with postoperative bleeding. Calibrated automated thrombogram (CAT) in platelet-poor plasma and rotational thromboelastometry (ROTEM) in whole blood were analyzed in patients scheduled for elective surgery due to severe AS (n = 103) and stable CAD (n = 68). Patients with AS displayed higher plasma thrombin potential, both thrombin peak with median 252 nmol/L (interquartile range 187-319) and endogenous thrombin potential (ETP) with median 1552 nmol/L/min (interquartile range 1340-1838), when compared to patients with CAD where thrombin peak was median 174 nmol/L (interquartile range 147-229) and ETP median 1247 nmol/L/min (interquartile range 1034-1448; both P < .001). Differences persisted after adjustment for age, gender, comorbidity, and antithrombotic treatment. Differences observed in thromboelastometry between the groups did not persist after adjustment for baseline characteristics. Bleeding amount showed no relationship with plasma thrombin potential but weakly to thromboelastometry ( R(2) = .064, P = .001). Patients with AS exhibited preoperatively increased plasma thrombin potential compared to patients with CAD. Plasma thrombin potential was not predictive for postoperative bleeding in patients scheduled for elective surgery.