In this ECG example of AIVR, note the right bundle branch block pattern and upward concordance, with all the QRS complexes up in the precordial leads V1 to V6 during the wide complex rhythm.

Ventricular tachycardia refers to a wide QRS complex heart rhythm — that is, a QRS duration beyond 120 milliseconds — originating in the ventricles at a rate of greater than 100 beats per minute.

Studies investigating QRS-complex abnormalities in association with cocaine use reported widened QRS-complex widths ... investigating cocaine-associated rhythm disturbances. Most of the studies ...