In general, APC resistance is not associated with ischaemic heart disease 2 or stroke. However, subgroup analysis reveals a 30-fold increased risk of acute myocardial infarction in young women who smoke or who are obese. There are reports of young women who are homozygous for the Factor V Leiden presenting with acute myocardial infarction but normal coronary arteries. 1 Regulation of coagulation activation and thrombophilia abnormalities. Activation of the blood coagulation system generates large amounts of thrombin which produce cleavage of fibrinogen to form a stable fibrin clot.
Natural anticoagulants downregulate the coagulation cascade.
This predisposes the patient to thrombosis. A point mutation in the prothrombin molecule causes an increase in its circulating plasma level predisposing to thrombus formation. It is estimated to increase the thrombotic risk by 4-fold compared to those without the mutation. The inheritance is autosomal dominant. A high concentration of homocysteine is an independent risk factor for atherothrombosis and venous thrombosis.