Wide QRS Tachycardia in WPW: When Antidromic AVRT Imitates VT

Atrioventricular Re-entry Tachycardia (AVRT) occurs in patients with accessory pathways (AP) via a re-entry circuit between the AV node and the AP. Anterograde conduction through the AP causes antidromic AVRT with wide QRS complexes, which may mimic ventricular tachycardia (VT). We report a 59-year-old male with ischemic cardiomyopathy (EF 35%) and recurrent wide QRS tachycardia who was referred for ICD implantation. Electrophysiology study identified a left posterolateral AP, and radiofrequency ablation successfully eliminated pre-excitation. ICD implantation was subsequently performed without complications. Antidromic AVRT should be considered in the differential diagnosis of wide QRS tachycardia, and catheter ablation remains a safe and effective treatment.