Final answer:
Low molecular weight heparins and fondaparinux work by enhancing antithrombin activity, which reduces clot formation. They are commonly used for preventing and treating DVT, PE, and ACS, especially in surgical patients and those requiring long-term anticoagulation without frequent monitoring.
Step-by-step explanation:
Low molecular weight heparins (LMWHs), such as enoxaparin and dalteparin, and fondaparinux work as anticoagulants by enhancing the activity of antithrombin. Antithrombin is a naturally occurring protein in the body that inactivates several enzymes of the coagulation system, primarily factor Xa, and to a lesser extent thrombin (factor IIa). LMWHs and fondaparinux bind to antithrombin and increase its activity, leading to a decrease in blood clot formation.
Their clinical application is primarily for the prevention and treatment of deep vein thrombosis (DVT) and pulmonary embolism (PE), among other conditions. These anticoagulants are especially valuable because they have predictable pharmacokinetics and do not require routine monitoring, in contrast to warfarin. They are commonly used in patients undergoing surgeries, particularly orthopedic surgeries, to prevent venous thromboembolism (VTE). Additionally, they are employed in the management of acute coronary syndromes (ACS) and in the treatment and secondary prevention of venous thrombosis.