Atriofascicular Mahaim with Ebstein anomaly: A case report

• Main Authors: Kazushi Ueshima, MD, Yoshihide Nakamura, PhD, Satoru Takeno, PhD, Toshiharu Miyake, PhD, Tsukasa Takemura, PhD
• Format: Article
• Language: English
• Published: Wiley 2017-10-01
• Series: Journal of Arrhythmia
• Subjects: Atriofascicular Mahaim; Ebstein anomaly; Electrophysiology study; Radiofrequency catheter ablation
• Online Access: http://www.sciencedirect.com/science/article/pii/S1880427617301266

We report a case of a 7-year-old girl with atriofascicular Mahaim (AFM) pathway concomitant with Ebstein's anomaly. The QRS wave showed left bundle branch block pattern on electrocardiogram. Holter electrocardiogram showed prolongation of the PR interval and QRS morphological change during sinus tachycardia. An electrophysiological study demonstrated that the distal His potential appeared earlier than the proximal His potential, which suggested retrograde His conduction toward the atrioventricular node. Conduction from the Mahaim fiber to the His bundle was faster than that from the atrioventricular node towards the His bundle. The findings of this important case allowed a differential diagnosis between AFM and Wolff-Parkinson-White (WPW) syndrome.