Ventricular ectopy from the non-coronary cusp: Pathophysiological and anatomical considerations

Area of Science:

• Cardiology
• Electrophysiology
• Cardiac Anatomy

Background:

• Ventricular arrhythmias (VAs) originating from the non-coronary cusp (NCC) are uncommon due to its limited myocardial contact.
• The NCC typically interfaces with the membranous septum near the His bundle, a common site for VAs.
• Understanding the precise origin of VAs is crucial for effective ablation strategies.

Observation:

• A young male patient presented with significant ventricular ectopy.
• Electrocardiographic and electrophysiological mapping localized the arrhythmogenic focus to the NCC.
• The prematurity of ectopy originating from the NCC was significantly greater than that from the peri-His region.

Findings:

• Successful radiofrequency ablation of ventricular ectopy originating from the NCC was achieved.
• The findings suggest the arrhythmogenic focus was not within the peri-His area.
• A myocardial extension adjoining the aortic root was identified as the likely source of the arrhythmia.

Implications:

• This case expands the understanding of rare arrhythmogenic substrates in the aortic root.
• It demonstrates the feasibility of ablating VAs originating from the NCC.
• Accurate localization of the arrhythmogenic focus is critical for successful catheter ablation in challenging anatomical locations.