Cerebral microembolization during atrial fibrillation ablation: comparison of different single-shot ablation...

Area of Science:

• Cardiology
• Neurology
• Medical Devices

Background:

• Clinically silent cerebral ischemia (SCI) occurs in 5-40% of patients undergoing pulmonary vein isolation (PVI).
• Initial studies reported high SCI rates with phased radiofrequency (RF) ablation using the pulmonary vein ablation catheter (PVAC).
• Recent procedural modifications have markedly reduced SCI incidence with PVAC.

Purpose of the Study:

• To analyze cerebral microembolization during phased RF ablation.
• To compare microembolization with two single-shot atrial fibrillation (AF) ablation technologies: cryoballoon (CB) and nMARQ™ multipolar irrigated RF ablation system.

Main Methods:

• Eighty-nine patients with AF underwent PVI.
• Patients were divided into groups based on phased RF ablation protocols (PVAC Group I, II, III) using different generator versions and modifications.
• Cerebral microemboli (MES) were assessed using transcranial Doppler during ablation with phased RF, CB, and nMARQ systems.

Main Results:

• MES counts decreased significantly with procedural modifications and newer RF generators in phased RF groups (PVAC Group I: 2703, Group II: 1087, Group III: 719).
• Cryoballoon ablation resulted in 1057 MES.
• The nMARQ system showed high MES counts (2166), comparable to initial phased RF (PVAC Group I).

Conclusions:

• Procedural modifications and updated RF generators significantly reduce cerebral microembolization during phased RF ablation.
• The nMARQ system demonstrated high microembolization rates, similar to early phased RF techniques.
• Optimizing ablation strategies is crucial for minimizing embolic events during PVI.