Left anterior hemiblock, LVH, LAH, and long PR
There are a number of abnormalities here.
- left anterior hemiblock
- QRS axis more left than -30 degrees
- initial R wave in the inferior leads (II, III and aVF)
- absence of any other cause of left axis deviation
- left ventricular hypertrophy
- In the presence of left anterior hemiblock the diagnostic criteria of LVH are changed. Rosenbaum suggested that an S wave in lead III deeper than 15 mm as predictive of LVH.
- long PR interval (also called first degree heart block)
- PR interval longer than 0.2 seconds
- left atrial hypertrophy
- M shaped P wave in lead II
- P wave duration > 0.11 seconds
- terminal negative component to the P wave in lead V1