Table 3: Diagnostic criteria for complete left bundle branch block.


QRS duration greater p95 or greater than 100 ms in children 4 to 16 years of age, and greater than 90 ms in children less than 4 years of age.


Broad notched or slurred R wave in leads I, aVL, V5 and V6 and an occasional RS pattern in V5 and V6 attributed to displaced transition of QRS complex.


Absent q waves in leads I, V5 and V6, but in the lead aVL, a narrow q wave may be present in the absence of myocardial pathology.


R peak time greater than 60 ms in leads V5 and V6, but normal in leads V1-3, when small initial r waves can be discerned in the above leads.


ST and T waves usually opposite in direction to QRS.