Fibrinolysis during cardiac surgery. Release of tissue plasminogen activator in arterial and coronary sinus blood.
Endothelial release of tissue plasminogen activator (t-PA) may initiate fibrinolysis. Fibrinolysis and coagulation were investigated in 12 patients undergoing elective coronary artery bypass surgery. Cardiopulmonary bypass (CPB) was 108 +/- 7 min (mean +/- SEM), the time of cold, crystalloid, retrograde cardioplegia 53 +/- 5 min. Arterial and coronary sinus blood were sampled concomitantly before cardioplegia and after release of the aortic cross-clamp, for measurement of t-PA antigen (Ag) and activity, plasminogen activator inhibitor (PAI-1) Ag and activity, t-PA/PAI-1 complex, single chain urokinase (sc-uPA) and urokinase (uPA) plasminogen activators, the fibrin split product D-dimer, thrombin-antithrombin complex (TAT), and the prothrombin split product F 1 + 2. Cardiopulmonary bypass significantly increased t-PA Ag and activity, t-PA/PAI complex, D-dimer, TAT, and F 1 + 2, and decreased PAI-1 Ag and activity in arterial blood; uPA and sc-uPA were unchanged. The tissue plasminogen activator antigen was higher in coronary sinus than arterial blood after 1 (39 +/- 5 vs 24 +/- 4 ng/ml, P < 0.003), 4 (P < 0.003), and 10 min (P < 0.004) reperfusion. Tissue plasminogen activator activity and t-PA/PAI complex increased, PAI-1 activity decreased, while all other parameters were unchanged across the coronary circulation. In conclusion, CPB induces fibrinolysis and coagulation. Cold cardioplegia induces t-PA release in the coronary circulation, denoting a postischemic antithrombotic function of the coronary endothelium. Tissue plasminogen activator may be used to evaluate endothelial stimulation or injury induced by CPB, or by different regimens of myocardial protection.
Valen
G
G
Department of Thoracic Surgery, Karolinska Hospital, Stockholm, Sweden.
Eriksson
E
E
Risberg
B
B
Vaage
J
J
D000368:Aged; D001158:Arteries; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D001026:Coronary Artery Bypass; D003331:Coronary Vessels / Q000378:metabolism; D004730:Endothelium, Vascular / Q000378:metabolism; D005342:Fibrinolysis; D006324:Heart Arrest, Induced; D006801:Humans; D008875:Middle Aged; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000097:blood*
D010959:Tissue Plasminogen Activator