Deep vein thrombosis, DVT (mechanism of disease)

This is a mechanism of disease flowchart for deep vein thromboses (DVT), covering the etiology, pathophysiology, pharmacology, and manifestations.

ADDITIONAL TAGS:
Lower extremity venous ultrasound: noncompressible obstructed vein, intraluminal hyperechoic mass, distention of affected vein. Doppler: absent/abnormal venous flow, inadequate augmentation of venous flow with distal calf compress or Valsalva
Generation of thrombus, typically in lower extremity proximal deep veins → DVT
Deep vein thrombosis
Medicine / iatrogenic
Infectious / microbial
Biochem / molecular bio
Inflammation / cell damage
Signs / symptoms
Labs / tests / imaging results
Risk factors / SDOH
Trauma
Blood flow physiology
Diet / nutrition
Genetics / hereditary
Neoplasm / cancer
Pathophysiology
+ pharmacology
Etiology
Manifestations
Virchow's triad
Venous stasis
Endothelial injury
Hypercoag-
ulable state
Bed rest
Immobility
Long travel
Indwelling cath
Recent surgery
Infection
Chronic disease
Prior VTE
Smoking
Lupus
IBD
Age 50
Thrombophilias (fVL)
Stroke
Cancer
Nephrotic syndrome
Obesity
Pregnancy
OCPs
Exposed collagen and/or endothelium damage
Accumulation of procoagulant coagulation cascade proteins
Defect or imbalance in coagulation cascade proteins
Renal loss of antithrombic factors
↑ estrogen, ↑ progesterone → ↑ prothrombin, ↑ fibrinogen, ↓ protein S
Varicose veins
Trauma
Intrinsic pathway:
[Surface contact (collagen, kallikrein, hmwk) → XIIa → XIa → IXa] + [thrombin → VIIIa]
Extrinsic pathway:
[Damage to endothelial tissue + tissue factor → IIIa] + VIIa
Common pathway:
[[X → Xa] + [thrombin → Va] → IIa → Ia] + [thrombin + XIIIa]
Stable fibrin clot
Coagulation cascade
Thrombin
Heparin, enoxaparin, fondaparinux, dabigatran
D dimer
Warfarin, phenprocoumon
Inhibit vitamin K epoxide redutase:
↓ II, VII, IX, X, C, S
Apixaban
Rivaroxaban
Alteplase
(tPA)
Plasminogen → plasmin
Swelling
Tightness
Heaviness
Dull pain (walk → worse, elevation → better)
Calf pain on dorsal flexion of the foot (Homans sign)
Fever
Patent foramen ovale
Stroke symptoms: Numb/weak extremities, confusion, speak / hear / vision deficit, etc
Stroke
Dyspnea
Chest pain
Dizziness
Weakness
DVT travels to lungs → occludes pulmonary arteries / arterioles
Pulmonary embolism
Unilateral
Bacteria
Suppurative thrombophlebitis
IV drug