Ventricular tachycardia is typically characterized by a wide QRS complex and a regular rhythm. The presence of an irregular rhythm with a wide QRS complex is more suggestive of a different condition, such as atrial fibrillation with aberrancy, where the irregular rhythm of the atria is conducted to the ventricles in an irregular pattern, resulting in a wide and irregular QRS complex. However, there are some forms of ventricular tachycardia that can be irregular, known as polymorphic ventricular tachycardia. This is less common and can be seen in certain conditions such as long QT syndrome, torsades de pointes, or in the context of certain drug toxicities or electrolyte imbalances. In summary, while ventricular tachycardia is generally regular, there are exceptions with polymorphic ventricular tachycardia being an irregular form. read more >>

If the rhythm pattern is irregular narrow-complex tachycardia, it is probably atrial fibrillation, possible atrial flutter, or multi-focal atrial tachycardia. Patient's rhythm has wide (> 0.12 sec) QRS complex AND Patient's rhythm is regular. Patient is in ventricular tachycardia or uncertain rhythm.read more >>