SEMINARS IN THROMBOSIS, THROMBOLYSIS, AND VASCULAR BIOLOGY .6. PROCOAGULANT STATES

Under normal physiologic conditions, blood flows freely within the coronary arteries and peripheral vasculature, providing oxygen and essential nutriments to vital organs and metabolically active tissues. The natural thromboresistant properties of the vascular endothelium and circulating blood components provide the ideal environment for this fundamental, life-sustaining process. While hemostasis is a vital defense mechanism, preventing blood loss and ensuring rapid vessel repair, nonphysiologic thrombosis or 'hemostasis in the wrong place' may impair blood flow enough to cause debilitating or life-threatening tissue damage. Procoagulant (prothrombotic) states promote nonphysiologic thrombosis and reflect one or more significant abnormalities in either the vessel wall, circulating blood, or plasma coagulation components themselves. Although a heightened thrombotic tendency may be the end result of a focal or systemic pathologic process, in either case, thromboembolic events involving the cardiovascular system may ensue.