Pathophysiology
Clinical meaning
The clinician must navigate complex anticoagulation decisions across multiple clinical scenarios. DOACs (dabigatran, rivaroxaban, apixaban, edoxaban) have largely replaced warfarin for non-valvular atrial fibrillation and VTE treatment due to predictable pharmacokinetics, fewer drug-food interactions, and no routine monitoring requirement. However, warfarin remains essential for mechanical heart valves and antiphospholipid syndrome. The choice of anticoagulant depends on indication, renal function, drug interactions, bleeding risk (HAS-BLED score), and patient factors. Reversal agents are now available for most anticoagulants: protamine for heparin, vitamin K and 4-factor PCC for warfarin, idarucizumab for dabigatran, and andexanet alfa for anti-Xa inhibitors. The clinician must prescribe, monitor, adjust, and manage transitions and complications across the anticoagulation spectrum.