Mechanism:

• Delayed conduction in the right bundle branch, secondary (delayed) excitation of the right ventricle via the left ventricular myocardium

ECG characteristics:

• QRS ≥ 0.12 s; discordance of the ventricular repolarization (ST segment and T wave)
  
• All axes
  
• QRS configuration: V1/2 – “rSR,” V5/6 – “qRS’”
  
• Turning point in V1: > 0.08 s

Etiology:

• Congenital, functional
  
• Right heart load (acute: pulmonary embolization; chronic: lung disease, shunt defects)

Treatment:

• Treatment of the underlying disease; no specific treatment of the rhythm

Differential diagnosis:

• Incomplete right bundle branch block
  
• Bifascicular block
  
• WPW syndrome

Differential diagnosis:

• Incomplete right bundle branch block
  
• Bifascicular block
  
• WPW syndrome

Differential diagnosis:

• Incomplete right bundle branch block
  
• Bifascicular block
  
• WPW syndrome

Mechanism:

• Delayed conduction in the right bundle branch, secondary (delayed) excitation of the right ventricle via the left ventricular myocardium

ECG characteristics:

• QRS 0.10–0.11 s; discordance of the ventricular repolarization (ST segment and T wave)
  
• All axes
  
• QRS configuration: V1/2 – “rSR,” V5/6 – “qRS’”
  
• Turning point in V1: > 0.08 s

Etiology:

• Congenital, functional
  
• Right heart load (acute: pulmonary embolization; chronic: lung disease, shunt defects)

Treatment:

• Treatment of the underlying disease; no specific treatment of the rhythm