High-density electroanatomic activation mapping to guide slow pathway modification in patients with persistent left...

Area of Science:

• Cardiology
• Electrophysiology
• Medical Imaging

Background:

• Slow pathway (SP) mapping and modification are challenging in patients with persistent left superior vena cava (PLSVC) due to anatomical variations.
• Limited studies exist on detailed 3D electroanatomic mapping (EAM) for guiding ablation in these complex cases.

Purpose of the Study:

• To describe a novel technique for SP mapping and ablation in sinus rhythm using 3D EAM.
• To validate this technique in patients with PLSVC after successful application in patients with normal coronary sinus (CS) anatomy.

Main Methods:

• Utilized high-resolution, ultra-high-density local activation timing mapping in sinus rhythm.
• Included seven patients with PLSVC and dual atrioventricular (AV) nodal physiology, and 21 control patients.
• Focused mapping on the right atrial septum and proximal CS.

Main Results:

• SP ablation targets were identified by latest activation times and specific electrogram characteristics in the right atrial septum.
• In PLSVC patients, targets were consistently found near the midanterior CS ostium.
• Successful SP modification was achieved with radiofrequency or cryoablation without complications.

Conclusions:

• High-resolution activation mapping in sinus rhythm aids in precise localization of SP ablation targets.
• This approach facilitates safe and effective SP ablation in patients with PLSVC.
• The described technique offers a valuable tool for managing complex AV nodal reentrant tachycardias in this patient population.