Diagnostic criteria of broad QRS complex tachycardia: decades of evolution.

Broad QRS complex tachycardia still presents a diagnostic challenge when confronted with a 12-lead electrocardiogram (ECG). The ECG differential diagnosis includes ventricular tachycardia vs. supraventricular tachycardia with functional aberration, pre-existing bundle branch block, intraventricular conduction disturbances, or pre-excitation. Despite all available criteria, broad complex tachycardias are still misdiagnosed or remain undiagnosed. This paper will briefly review the most recognized criteria.