202406270457

Status:

Tags: ECG

left posterior fascicular block

right axis deviation
lead I & aVL : rS
III : qR

less common than LAFB ∵ broad bundle more resistant to damage
need to r/o other causes of RAD first

Guideline definition

  1. Frontal plane axis between 90° and 180° in adults.
    • Owing to the more rightward axis in children up to 16 years of age, this criterion should only be applied to them when a distinct rightward change in axis is documented.
  2. rS pattern in leads I and aVL.
  3. qR pattern in leads III and aVF.
  4. QRS duration less than 120 ms.

References

AHA/ACCF/HRS recommendations for the standardization and interpretation of the electrocardiogram: part III: intraventricular conduction disturbances: a scientific statement from the American Heart Association Electrocardiography and Arrhythmias Committee, Council on Clinical Cardiology; the American College of Cardiology Foundation; and the Heart Rhythm Society. Endorsed by the International Society for Computerized Electrocardiology. J Am Coll Cardiol. 2009 Mar 17;53(11):976-81.