Right bundle branch block

(Redirected from RBBB)


Bundle Branch Block.png
  • QRS > 0.12 in limb leads
  • Triphasic QRS (rSR') or biphasic (qR), often with ST depression & TWI in V1-V3
    • V1 must have a positive complex
    • Second R wave in V1 is always taller than the first (rSR')
  • Slurred S in 1 and V6
  • ST depression and TWI in other leads should arouse suspicion
  • Any ST elevation is abnormal in RBBB and must prompt evaluation for STEMI
RBBB V1 Morphologies

Differential Diagnosis

Wide-complex tachycardia

Assume any wide-complex tachycardia is ventricular tachycardia until proven otherwise (it is safer to incorrectly assume a ventricular dysrhythmia than supraventricular tachycardia with abberancy)

^Fixed or rate-related

See Also


  • Journal of Electrocardiology. Vol 43 (2010). 40-42.