Mechanism Thrombophilia

the coagulation system, described cascade , consists of group of proteins interact in formation of fibrin-rich clot.

thrombosis multifactorial problem because there multiple reasons why person might develop thrombosis. these risk factors may include combination of abnormalities in blood vessel wall, abnormalities in blood flow (as in immobilization), , abnormalities in consistency of blood. thrombophilia caused abnormalities in blood consistency, determined levels of coagulation factors , other circulating blood proteins participate in coagulation cascade .

normal coagulation initiated release of tissue factor damaged tissue. tissue factor binds circulating factor viia. combination activates factor x factor xa , factor ix factor ixa. factor xa (in presence of factor v) activates prothrombin thrombin. thrombin central enzyme in coagulation process: generates fibrin fibrinogen, , activates number of other enzymes , cofactors (factor xiii, factor xi, factor v , factor viii, tafi) enhance fibrin clot. process inhibited tfpi (which inactivates first step catalyzed factor viia/tissue factor), antithrombin (which inactivates thrombin, factor ixa, xa , xia), protein c (which inhibits factors va , viiia in presence of protein s), , protein z (which inhibits factor xa).

in thrombophilia, balance between procoagulant , anticoagulant activity disturbed. severity of imbalance determines likelihood develops thrombosis. small perturbances of proteins, such reduction of antithrombin 70–80% of normal level, can increase thrombosis risk; in contrast hemophilia, arises if levels of coagulation factors markedly decreased.

in addition effects on thrombosis, hypercoagulable states may accelerate development of atherosclerosis, arterial disease underlies myocardial infarction , other forms of cardiovascular disease.