Which technology is best for catheter ablation of paroxysmal AF?

Paroxysmal AF is defined as AF that comes and goes on its own, lasts for less than a week and typically does not require cardioversion.

Once stroke risk has been quantified and addressed (with anticoagulation where necessary), the goal of treatment is primarily to improve the symptoms which the AF causes. These can include palpitations, shortness of breath, fatigue, lethargy and dizziness. Typically we try medications in the first instance (either regularly or as needed – “pill-in-the-pocket”). However these medications often do not abolish symptoms and then catheter ablation is considered.

In around 95% of people who have paroxysmal AF, this originates as a result of ectopic beats originating from the pulmonary veins, which are extra electrical impulses which trip the heart up to go out of rhythm; this was originally described in the late 1990s. This led to a treatment strategy called pulmonary vein isolation. The intention of this approach is to cause deliberate localised damage to the wall of the heart where these extra electrical impulses come into the heart so as to stop them from being able to trigger AF.

You can read more about this in the catheter ablation of AF section.

There are now three different technologies we can use in order to isolate the pulmonary veins – radio-frequency (RF) ablation, cryo-ablation and pulsed field ablation (PFA). RF ablation involves causing small localised burns whereas cryo-ablation involves freezing the part of the heart (in this case, the left atrium) allowing AF to occur. Pulsed field ablation (PFA) involves using high-energy electrical pulses in order to target the areas around the pulmonary veins. This approach is faster and has equivalent success rates, but also minimises the risk of damage to surrounding structures.