Deep Vein Thrombosis
A blood clot forming in a deep vein, usually in the legs. DVT can lead to potentially fatal pulmonary embolism. Bivalirudin (a direct thrombin inhibitor peptide) is used as an anticoagulant during cardiac procedures. Eptifibatide (a platelet aggregation inhibitor) prevents clot formation in acute coronary syndromes.
Technical Context
DVT pathophysiology (Virchow's triad): venous stasis, endothelial injury, and hypercoagulability. Anticoagulant peptide drugs: bivalirudin (direct thrombin inhibitor — binds both the catalytic site and exosite 1 of thrombin; used during PCI as an alternative to heparin, with a short half-life of ~25 minutes allowing rapid offset; the HORIZONS-AMI and EUROMAX trials established its role in acute coronary intervention) and eptifibatide (platelet glycoprotein IIb/IIIa antagonist — prevents fibrinogen-mediated platelet aggregation; used in acute coronary syndromes and PCI). While heparin (a glycosaminoglycan, not technically a peptide) remains the standard anticoagulant for DVT, the peptide-based thrombin inhibitor bivalirudin offers advantages in HIT (heparin-induced thrombocytopenia) where heparin is contraindicated.