Simple periprocedural precautions to reduce Doppler microembolic signals during AF ablation

Area of Science:

• Cardiology
• Neurology
• Medical Imaging

Background:

• Atrial fibrillation (AF) ablation procedures can generate microembolic signals (MES) despite preventative measures.
• Understanding the sources and contributing factors of MES is crucial for patient safety during AF ablation.

Purpose of the Study:

• To investigate the incidence and characteristics of MES during AF ablation.
• To determine the relationship between MES and procedure time, specific procedural steps, activated clotting time (ACT), and catheter contact force.

Main Methods:

• A prospective trial involving 53 AF patients undergoing pulmonary vein isolation using irrigated, point-by-point radiofrequency ablation.
• Continuous transcranial Doppler (TCD) monitoring of middle cerebral arteries throughout the ablation procedure.

Main Results:

• An average of 686±226 MES were detected, with 569±208 gaseous and 117±31 solid.
• The highest number of MES occurred during radiofrequency (RF) ablation (439±192 gaseous, 41±22 solid).
• Fewer MES were observed with shorter procedure times, higher ACT, and the use of contact force monitoring.

Conclusions:

• AF ablation with irrigated RF catheters generates significant MES, primarily during RF application.
• MES are influenced by total procedure duration and achieved ACT.
• Contact force monitoring may be a strategy to reduce MES during AF ablation.