LAFB (Left anterior fasicular block)
Patient. 78 year old female was admitted 20 hours after chest pain. She was diagnosed having anterior MI. Cardiac catheterization showed high grade complex stenosis involving the distal left main and proximal LAD. There was also 80% stenosis of OM and PDA. She was thought not to be a good candidate for interventional treatment. Patient had recurrent severe chest pain and was taken back to cardiac catheterization laboratory where she underwent successful angioplasty and stenting of her distal left main and proximal LAD. Other diagnosis were type 2 diabetic, hypertension, hyperlipidemia and moderate bilateral renal artery disease.

LAFB Criteria: 
Frontal plane QRS axis between -45 and -90
rS pattern in leads II, III, and aVF
 • qR in aVL
QRS duration is < 120 msec. (In case of intermittent LAFB, the QRS duration may increase up to 20 msec during LAFB)

 - LAFB is not synonym with LAD
 - LAD may be found in various conditions
 - Interesting right arm and left leg lead switch in this case

Axis on frontal planeDegree

1. Normal
Left axis deviation (LAD)
3. Right axis deviation (RAD)
4. Extreme axis deviation
5. Indeterminate axis
6. Vertical axis

7. Horizantal axi

1. Between - 30 and + 90
2. More negative than - 30
3. More positive than + 90
4. Between - 90 and - 180
5. All limb leads has biphasic QRS

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