What does an extended p-q interval of an ecg usually indicated?

AV node delay: I think you might be referring to a prolonged pr interval. This refers to the time between when the atrium activates and when the ventricle activates. If this is prolonged, it could indicate a problem (either benign or more ominous) with the atrioventricular node or his-purkinje system, the specialized structures in the heart responsible for conducting signals from the atria to ventricles.