Vessel

Superior Vena Cava Obstruction

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Superior Vena Cava Obstruction, Superior Caval Vein Obstruction, Superior Vena Cava Occlusion, Superior Vena Cava Syndrome, SVC Syndrome

  • Pathophysiology
  1. Superior Vena Cava Obstruction to flow
    1. Internal Vascular Invasion (e.g. Vena cava thrombosis , tumor infiltration
    2. External Compression (e.g. right lung or Mediastinal Mass)
      1. Mediastinal Mass gradually compresses superior vena cava, blocking entry into right atrium
      2. Results in retrograde flow and regional edema
  2. Superior Vena Cava Obstruction Compensation
    1. SVC is a thin walled, low pressure large vein 2 cm in width and 4-6 cm in diameter
    2. High venous pressures within SVC may be compensated with collateral circulation over 1-2 weeks
      1. Example: Azygous vein may provide some collateral drainage
  • Causes
  1. Malignancy (60% of all cases)
    1. Bronchogenic Carcinoma (80% of malignancy causes)
    2. Malignant Lymphoma (15% of malignancy causes)
    3. Metastatic Disease (to lung, mediastinum or lymph nodes)
      1. Breast adenocarcinoma
      2. Testicular seminoma
  2. Vena Cava thrombosis (majority of non-malignant cases)
    1. Long-term venous catheters (40% of thrombosis cases)
    2. Idiopathic
    3. Behcet's Syndrome
    4. Polycythemia Vera
    5. Paroxysmal Nocturnal Hemoglobinuria
    6. Long-term shunts
    7. Long-term Pacemakers
  3. Other Benign Disease (Rare)
    1. Mediastinal fibrosis
      1. Post-Radiation Therapy
      2. Idiopathic
      3. Histoplasmosis
      4. Actinomycosis
      5. Tuberculosis
    2. Benign Mediastinal tumor
      1. Aortic aneurysm
      2. Dermoid tumor
      3. Goiter
      4. Sarcoidosis
  • Symptoms
  1. Dyspnea (50%)
  2. Neck and facial swelling (40-82%)
    1. Head fullness or pressure sensation
  3. Swelling of trunk and upper extremities (40%)
  4. Local Airway Compression
    1. Cough
    2. Dysphagia
    3. Choking sensation
    4. Hoarseness
  5. Headache
    1. Common presenting complaint
    2. Secondary to Increased Intracranial Pressure
  6. Referred Pain
    1. Chest Pain
    2. Shoulder Pain
  7. Miscellaneous
    1. Lacrimation
    2. Visual changes
    3. Syncope
  • Signs
  1. Thoracic vein distention (65%)
  2. Neck vein distention (55%)
  3. Facial edema (55%)
  4. Tachypnea (40%)
  5. Plethora of the face and Cyanosis (15%)
  6. Edema of upper extremities (10%)
  7. Paralysis of Vocal Cords (3%)
  8. Horner's Syndrome (3%)
  9. Distended antecubital veins
  • Associated Conditions
  • Imaging
  1. Chest XRay
    1. Mass identified in 90%
    2. Right superior mediastinum widening (75%)
    3. Hilar Adenopathy (50%)
    4. Right Pleural Effusion (25%)
  2. Chest CT with IV Contrast
    1. Identifies mass lesions and sites of SVC obstruction
    2. Collateral vessel development is a sensitive and specific marker of SVC Syndrome
      1. Test Specificity: 96%
      2. Test Sensitivity: 92%
  3. Other Imaging modalities
    1. MR Venogram
    2. Cavogram
    3. Ultrasound
  • Management
  1. Severity of airway and vascular compromise varies by timing of progression
    1. Rapid progression may not allow for compensation, resulting in acute airway compromise
  2. Supportive care for airway compromise
    1. ABC Management
    2. High-Dose Corticosteroids
    3. Elevate the head of the bed
    4. Avoid Diuretics
  3. Identify mass etiology
  4. Reduction in mass size
    1. Emergent Intervention Radiology
    2. Other modalities
      1. Radiation Therapy (e.g. Non-Small Cell Lung Cancer)
      2. Chemotherapy
      3. Surgical decompression
  5. Consult Oncology and Cardiothoracic Surgery acutely
    1. Palliative CareConsultation once stabilized
  6. Anticoagulation with Heparin
    1. Indicated for venous thrombosis
  7. Intravenous stenting
    1. Common acute management
    2. Improvement is seen within days
    3. Effective even when tumor mass is not reducible
  • Prognosis
  1. Poor prognostic sign
    1. Predicts 90% mortality in 3 years
    2. Median survival: 6 months
  • References
  1. Long, Long and Koyfman (2020) Crit Dec Emerg Med 34(11): 17-24
  2. Higdon (2018) Am Fam Physician 97(11):741-8 [PubMed]