Cryosurgical ablation of the A-V node-His bundle: a new method for producing A-V block

Area of Science:

• Cardiovascular Science
• Interventional Cardiology
• Cryobiology

Background:

• Drug-resistant supraventricular tachycardias pose significant clinical challenges.
• Current ablation techniques carry risks, necessitating exploration of alternative methods.
• Atrioventricular conduction requires precise targeting for effective arrhythmia control.

Observation:

• A cryosurgical instrument was employed to ablate atrioventricular conduction.
• Initial cooling to 0°C induced reversible heart block in patients.
• Subsequent controlled freezing to -60°C resulted in persistent atrioventricular conduction block.

Findings:

• Cryoablation of the His bundle area produced complete, persistent heart block in clinical cases.
• The cryolesion demonstrated safety, with no rupture, aneurysm formation, or valvular dysfunction.
• Postoperative evaluation revealed stable pacemaker function originating proximal to the His bundle branching.

Implications:

• Cryosurgery presents a promising, potentially safer alternative for ablating atrioventricular conduction.
• This technique could be applied to target various cardiac dysrhythmia sources, including ectopic foci and accessory pathways.
• Further research may establish cryoablation as a standard treatment for refractory supraventricular tachycardias.