Coexistence of a Classical Nodoventricular Accessory Pathway With a Left-Sided Mahaim Accessory Pathway

Area of Science:

• Cardiology
• Electrophysiology
• Cardiac Anatomy

Background:

• Mahaim pathways are accessory atrioventricular connections that can cause arrhythmias.
• The presence of multiple Mahaim pathways poses diagnostic challenges in clinical electrophysiology.
• Accurate identification of accessory pathways is crucial for effective arrhythmia management.

Observation:

• A case of coexisting Mahaim pathways is presented.
• Standard electrocardiographic criteria were insufficient for definitive pathway identification.
• Specific interval measurements were analyzed during electrophysiological study.

Findings:

• Septal-Hisian (SH) and Hisian-atrial (HA) intervals proved valuable in differentiating the Mahaim pathways.
• These intervals aided in identifying concealed nodoventricular and His-ventricular connections.
• The findings suggest a novel diagnostic approach for complex accessory pathway coexistence.

Implications:

• This case highlights the utility of SH/HA intervals for diagnosing concealed Mahaim pathways.
• The study contributes to the understanding of accessory pathway anatomy and electrophysiology.
• Improved diagnostic methods can lead to more targeted and successful ablation strategies for patients with complex arrhythmias.