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Common Congenital Heart Lesions - page 120 / 126





120 / 126

120 of 126

Physical Findings:

  • With proximal DVT, will see edema of involved leg.

  • May see erythema.

  • May feel localized warmth.

  • When palpate, may find:

    • o

      tenderness over the course of the phlebitic vein

      • o

        deep venous cord (stiff cord-like quality along the thrombosed vessel)

  • Homan’s Sign: non-specific/unreliable finding of DVT that when dorsiflex patient’s foot, they have calf pain


  • Remember good ‘ol Virchow and his triad of factors that predispose to venous thrombosis:

    • 1.

      stasis of blood flow: disrupts laminar flow and puts platelets in contact w/ endothelium allowing coagulation factors to accumulate and slowing influx of clotting inhibitors

    • 2.

      hypercoagulability: often from genetic disorders or cancers

    • 3.

      vascular damage: “peels back” (denudes) the endothelium to expose subendothelial collagen, which is a substrate for binding von Willebrand’s factor and platetlets Æ initiates clotting cascasde and leads to clot formation.

      • Even if endothelium isn’t denuded, but is only injured, can get endothelial dysfunction, which can prevent synthesis and secretion of endothelial vasodilating substances and allow thrombosis to happen

  • Note: Refer to the etiology section directly below to see what can precipitate problems in each part of the triad.

  • DVT occurs most commonly in the veins of calves – may also develop in proximal veins (popliteal, femoral, iliac)

  • Left untreated, 20-30% of DVTs occurring in calves propagate to proximal veins.

  • Two major consequences of DVT:

    • 1.

      Pulmonary Embolism: a clot dislodges and travels through the IVC and right heart into the pulmonary circulation, where it causes obstruction.

    • 2.

      Postphlebitic syndrome: chronic deep venous insufficiency – persistent occlusion by DVT

Etiology & some Epidemiology:

  • Predisposing factors: related to…stasis of blood flow (red), hypercoagulable states (purple), vascular damage (blue)

    • o

      Prolonged immobilization/inactivity (after surgery, long travel in car or plane)

      • o

        Immobilization of an extremity (after bone fracture)

      • o

        Cardiac failure

      • o

        Hyperviscosity syndromes

      • o

        Inherited coagulation disorders (e.g. Factor V Leiden)

      • o

        Antiphospholipid antibodies/lupus anticoagulant

      • o

        Neoplastic disease (pancreatic, lung, stomach, breast cancers)

      • o


      • o

        Oral contraceptive use (or other high estrogen states)

      • o

        Myeloproliferative diseases

      • o


      • o

        Instrumentation (intravenous catheters)

      • o

        Trauma (external injury)

  • PEs are the main complication of DVT; the incidence of PE in the US is 600,000 per year.

  • 30-40% of PEs are fatal if untreated.

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