OBJECTIVE: We hypothesized that antithrombotic plasma-activated protein C plays a defensive antithrombotic role during coronary ischemia and postischemic reperfusion. METHODS AND RESULTS: We evaluated protein C activation during cardiopulmonary bypass and coronary reperfusion in 20 patients undergoing coronary bypass surgery. During cardiopulmonary bypass and during the 10 minutes after aortic unclamping, the plasma levels of protein C (mean +/- standard error of the mean) decreased from 123% +/- 7% to 74% +/- 5% of normal mean. In contrast, the levels of activated protein C in plasma increased from 122% +/- 8% to 159% +/- 21%, and the activated protein C/protein C ratio increased from 1.04 +/- 0.08 to 2.29 +/- 0. 31 (P =.006, 2-tailed Wilcoxon signed rank test). Patients were stratified on the basis of the increase in activated protein C in the coronary sinus plasma at 10 minutes after reperfusion by means of the arbitrary value of 1.5 for the activated protein C/protein C ratio. Within 24 hours, the patients with low increases in activated protein C (ratio < 1.5, n = 8) had a significantly (P <.05) lower cardiac output and mean pulmonary artery pressure, as well as a higher systemic vascular resistance, than patients (n = 11) with high increases in activated protein C (ratio > 1.5). The rapid increase in activated protein C during the first 10 minutes after aortic unclamping indicated protein C activation in the reperfused vascular beds. CONCLUSIONS: The antithrombotic protein C pathway was significantly activated during cardiopulmonary bypass mainly during the minutes after aortic unclamping in the ischemic vascular beds. Suboptimal protein C activation during ischemia may impair the postischemic recovery of human heart and circulation.
OBJECTIVE: We hypothesized that antithrombotic plasma-activated protein C plays a defensive antithrombotic role during coronary ischemia and postischemic reperfusion. METHODS AND RESULTS: We evaluated protein C activation during cardiopulmonary bypass and coronary reperfusion in 20 patients undergoing coronary bypass surgery. During cardiopulmonary bypass and during the 10 minutes after aortic unclamping, the plasma levels of protein C (mean +/- standard error of the mean) decreased from 123% +/- 7% to 74% +/- 5% of normal mean. In contrast, the levels of activated protein C in plasma increased from 122% +/- 8% to 159% +/- 21%, and the activated protein C/protein C ratio increased from 1.04 +/- 0.08 to 2.29 +/- 0. 31 (P =.006, 2-tailed Wilcoxon signed rank test). Patients were stratified on the basis of the increase in activated protein C in the coronary sinus plasma at 10 minutes after reperfusion by means of the arbitrary value of 1.5 for the activated protein C/protein C ratio. Within 24 hours, the patients with low increases in activated protein C (ratio < 1.5, n = 8) had a significantly (P <.05) lower cardiac output and mean pulmonary artery pressure, as well as a higher systemic vascular resistance, than patients (n = 11) with high increases in activated protein C (ratio > 1.5). The rapid increase in activated protein C during the first 10 minutes after aortic unclamping indicated protein C activation in the reperfused vascular beds. CONCLUSIONS: The antithrombotic protein C pathway was significantly activated during cardiopulmonary bypass mainly during the minutes after aortic unclamping in the ischemic vascular beds. Suboptimal protein C activation during ischemia may impair the postischemic recovery of human heart and circulation.
Authors: Outi Lindstrom; Leena Kylanpaa; Panu Mentula; Pauli Puolakkainen; Esko Kemppainen; Reijo Haapiainen; Jose A Fernandez; John H Griffin; Heikki Repo; Jari Petaja Journal: Crit Care Date: 2006-02 Impact factor: 9.097
Authors: Katrina K Ki; Margaret R Passmore; Chris H H Chan; Maximilian V Malfertheiner; Jonathon P Fanning; Mahé Bouquet; Jonathan E Millar; John F Fraser; Jacky Y Suen Journal: Intensive Care Med Exp Date: 2019-08-20
Authors: Karin C A A Wildhagen; Roy Schrijver; Linda Beckers; Hugo ten Cate; Chris P M Reutelingsperger; Esther Lutgens; Gerry A F Nicolaes Journal: PLoS One Date: 2014-07-17 Impact factor: 3.240