Uncommon Cause of Wide QRS Complex Tachycardia, Mahaim Tachycardia Revisited

Patients who present with wide complex tachycardia are always challenging both diagnostically and therapeutically. Mahaim fiber is an uncommon cause of tachycardia in which cardiac pre-excitation occurs via slow-conducting, long accessory pathways that terminate in the right ventricular free wall or into the adjacent right bundle.