Whilst anti-arrythmic drugs (AAD) are not without morbidity or mortality,  and radiofrequency ablation requires mutliple lesions and can be associated with complications, cryoablation offers PVI with a single continuous cryolesion.

But what are the complications?

The safety and efficacy of this novel technique was explored in the STOP-AF trial.

245 patients randomised to cryoablation or AAD with 163 in the cryo arm and 82 in the AAD arm. Some patients did have cavo-tricuspid isthmus ablation too.

The patients were symptomatic with AF (a large number actually had futter) and had previously failed at least one AAD.

Procedural success was 98.2%. There was a lot of cross over from the AAD group to cryoablation.

Procedural complications with cryo was 6.3%- pulmonary vein stenosis, phrenic nerve palsy.

Freedom from AF was significantly better in the cryo arm.

So, this looks a promising new technique but a few words of caution: there was a mixed bag of patients here- AF and AFlutter, some had the additional cryo-tricuspid isthmus ablation as well  as PVI. Waters a bit muddy! Seems like a steep learning curve with this too, the complication of phrenic nerve palsy is concerning. We need a randomised control trial of cryo vs conventional PVI in AF to real clear the waters here!

Click here for the trial summary and presentation slides of the session.