Freezor

How It Works

Cryoablation

Cryoablation is a therapy that uses the removal of heat from tissue to treat cardiac arrhythmias. It restores normal electrical conduction by freezing the cardiac tissue or pathways that interfere with the normal distribution of the heart’s electrical impulses.

During a cardiac ablation procedure, a pressurized refrigerant, liquid nitrous oxide (N₂O), is delivered from a tank in the CryoConsole. The liquid refrigerant travels in an ultra-fine tube through the coaxial umbilical and the shaft of the Freezor^® CryoAblation Catheter to the tip of the catheter.

The liquid refrigerant vaporizes as it is sprayed into the tip. As it vaporizes, it absorbs heat from the surrounding tissue, thereby cooling and freezing the target tissue. The warmed refrigerant is vacuumed back to the CryoConsole through a lumen within the shaft of the catheter and coaxial umbilical. The CryoConsole discharges the vapor into the hospital scavenging system.

Freezor can create temperatures at its tip as low as -75ºC inside a beating heart. It offers a site-testing capability – which involves a technique called cryomapping – which may aid physicians to avoid unwanted electrophysiological effects on AV node conduction.

Cryomapping

In Cryomapping mode, the CryoAblation system temporarily chills conducting tissue in the target area, creating a reversible electrical effect. This allows for precise site testing and confirmation prior to proceeding with definitive ablation. This is helpful when performing AVNRT procedures.

Cryomapping Animation (0:44, 8.6 MB)
CryoMapping demonstration for catheter ablation using focal cryoablation

Cryoadhesion

Cryoadhesion maintains the position of the catheter tip in the beating heart, as the tip firmly attaches to the endocardium upon freezing. Cryoadhesion also facilitates the use of pacing to test for effect and prevents the accidental dislodgement of the catheter in the event of abrupt changes in rhythm.

CryoAdhesion Animation (0:14, 2.7 MB)
Cryoadhesion demonstration for catheter ablation using focal cryoablation