J Wave


J Wave, J-Wave, Osborn Wave, J Wave Syndrome

  • Definitions
  1. J Point (Junction Point)
    1. Junction between end of QRS Complex and begining of ST Segment
  2. J Wave
    1. Terminal slurring of the QRS Complex
    2. Deflection that forms at junction of QRS Complex and ST Segment, esp. lateral and precordial leads
    3. May appear as slurring or notch within the QRS (prior to the J Point and onset of ST Segment)
    4. J Wave may be upright or inverted
  • Causes
  • J Wave Syndromes
  1. Early Repolarization Syndrome
  2. Brugada Syndrome
  3. Hypothermia (Temperature <32 C)
    1. J Wave amplitude increasing as core Temperature drops, and resolves with rewarming
    2. Associated with prolonged intervals (PR, QRS, QT), Sinus Bradycardia or Atrial Fibrillation
  • Causes
  • Other J Wave causes
  1. Myocardial Ischemia
  2. Sepsis
  3. Hypercalcemia
  4. Normal variant in some young patients
  5. CNS disorder
    1. Subarachnoid Hemorrhage
    2. Closed Head Injury
  • Differential Diagnosis
  1. Right Bundle Branch Block (RBBB)
    1. J Wave Type I (wide, large J Wave in leads V1-3) may appear similar to RBBB
    2. However, QRS Duration is not wide in lateral leads in J Wave (contrast with wide in RBBB)
  • References
  1. Mattu (2018) Crit Dec Emerg Med 32(7): 14