Introduction:

l  Disease spectrum from asymptomatic deep vein thrombosis to massive pulmonary embolism causing immediate death.

l  About 79% of patients with pulmonary embolism have evidence of legs’ deep venous thrombosis.

l  Pulmonary embolism occurs in up to 50% of patients with proximal deep venous thrombosis

l  Pulmonary infarction is not usually present due to the dual circulation arising from the pulmonary and bronchial arteries.

 

Pathophysiology

l  Anatomical obstruction cause compromised physiology

l  Release of vasoactive and bronchoactive agents lead to deleterious ventilation–perfusion matching

l  RV afterload increases, RV wall tension rises and lead to dilatation, dysfunction, and ischemia of the RV

l  Death results from right ventricular failure

 

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Risk  factors-acquired

l  Antiphospholipid antibody syndrome

l  Oral contraceptives

l  Hormone-replacement therapy

l  Chemotherapy

l  Obesity

l  Central venous catheterization

l  Immobilizer or cast

l  Reduced mobility

l  Advanced age

l  Cancer

l  Acute medical illness

l  Major surgery

l  Trauma

l  Spinal cord injury

l  Pregnancy and postpartum period

l  Polycythemia vera

 

Risk factors - Hereditary

l  Antithrombin deficiency

l  Protein C deficiency

l  Protein S deficiency

l  Factor V Leiden

l  Activated protein C resistance without factor V Leiden

l  Prothrombin gene mutation

l  Dysfibrinogenemia

l  Plasminogen deficiency

 

      Clinical manifestation

l  Tachypnea and tachycardia-- Common but nonspecific

l  Pleuritic chest pain and hemoptysis -- Frequent in pulmonary infarction ( smaller, more peripheral emboli, and may with pleural rub).

l  Leg pain, warmth, or swelling-- Symptoms of DVT

l  Elevated neck veins, a loud P2, a right-sided gallop, and right ventricular lift

l Pulmonary hypertension

l  All signs and symptoms are neither sensitive nor specific.

l  Clinical symptoms didn’t correlate with disease severity

l  The possibility of massive pulmonary embolism should be considered in pts with sudden onset of near syncope or syncope, hypotension, extreme hypoxemia, electromechanical dissociation or cardiac arrest.

     Image study     GPULMONARY_EMBOLISM_PE_FIG1.jpg

l  Ventilation–perfusion scanning

l  Contrast-enhanced CT

l  Magnetic resonance imaging (MRI)

l  Standard pulmonary arteriography

l  Imaging for detecting DVT

l  Echocardiography

 

     Chest radiograph shows bilateral pleural effusion and long linear bands of atelectasis (Fleischner lines)
      (arrows).
      pepic1.jpg
     Fig 1. Spiral CT of patient showing large thrombus (arrowed) within the left pulmonary artery
     Diagnostic approach
  
   圖片2.jpg
        Treatment algorithm
      圖片3.jpg
      簡報檔按此(密碼提示:將近百分之多少的肺栓塞病患有足部的DVT)
  

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