Penetrating cardiac injury

Background

  • Ventricles are at greatest risk due to anterior location
    • RV (involved in 40% of injuries)
    • LV (involved in 35% of injuries)
    • RA (involved in 20% of injuries)
    • LA (involved in 5% of injuries)

Clinical Features

  • Stab wounds
    • Usually affect heart if enter via the "cardiac box"
      • Chest area bounded by sternal notch, xiphoid, and nipple
  • Gun shot wound can affect heart even if enters at distant site

Differential Diagnosis

Thoracic Trauma

Evaluation

Workup

Pericardial fluid on ultrasound
Transthoracic echo of pericardial fluid showing "swinging heart"
  • FAST exam
    • First view of FAST in penetrating injury should be pericardial
    • Pericardial fluid detection (Sn 100%, Sp 97%)
      • In acute cases, even a relatively small build up of pericardial fluid can lead to hemodynamic compromise
      • Differentiate pericardial effusion from pleural effusion using the parasternal long axis view. Pericardial effusions will have an anechoic stripe between the left atrium and descending thoracic aorta. In a pleural effusion, the stripe will be seen behind the descending thoracic aorta.[1]
  • CTA
    • Imaging study of choice for penetrating and blunt trauma

Management

Cardiac tamponade

  • Most often results from stab wounds; up to 80% of myocardial stab wounds may develop cardiac tamponade
  • GSW less likely to develop into tamponade because it is more difficult for the pericardium to seal the defect (larger, more irregular in shape) [2]

Cardiac missiles

  • Those that cause BP instability, free or partially exposed should be removed
  • Most intramyocardial and intrapericadrial bullets can be left in place

Disposition

  • Admit

See Also

References

  1. Randazzo MR et al. Acad Emerg Med, 2003. PMID: 12957982
  2. Tintinalli's

Authors:

Ross Donaldson