LEFT POSTERIOR FASCICULAR BLOCK (LPFB)/LEFT POSTERIOR HEMIBLOCK (LPHB):

An electrical delay or blockage in the conduction pathway that sends impulses down the left posterior fascicle of the left bundle.

•ECG Criteria:

•Prolonged QRS (0.08-0.11 sec).

•Leads 1 and aVL: small R waves and deep S waves.

•Leads 2, 3 and aVF: small Q waves and tall R waves.

•No other explanation for the right axis deviation (e.g. right ventricular hypertrophy or anterior wall myocardial infarction).