A new study says early intervention with cryoballoon catheter ablation (cryoablation) can halt disease progression and reduce risk of serious health impacts of atrial fibrillation(AF).

Atrial fibrillation affects about 3 percent of the population and is a common heart rhythm problem linked to increased risk of stroke and heart failure. Those are serious and a new analysis finds that there were fewer serious adverse outcomes with catheter cryoablation. Cryoablation involves guiding a small tube into the heart to kill problematic tissue with cold temperatures - it is usually reserved as a secondary treatment when patients don’t respond to antiarrhythmic drugs. Atrial fibrillation is a risk factor for the more serious outcome, not causal, so the protocol is to try antiarrhythmic drugs first before an invasive surgical procedure. 

The authors argue it may be better to start with the fallback treatment because while the condition starts as an isolated electrical disorder, each recurring incident can cause electrical and structural changes in the heart that can lead to longer-lasting events, for days.

Credit: Medtronic

Because cryoablation targets and destroys the cells that initiate and perpetuate AF, the researchers say it can lead to longer-lasting benefits. For the trial, the team enrolled 303 patients with AF at 18 sites across Canada. Half of the patients were randomly selected to receive antiarrhythmic drugs, while the other half were treated with cryoablation. All patients received an implantable monitoring device that recorded their cardiac activity throughout the study period.

After three years, the researchers found that patients in the cryoablation group were less likely to progress to persistent AF compared to patients treated with antiarrhythmic drugs. Over the follow-up period, the cryoablation patients also had lower rates of hospitalization and experienced fewer serious adverse health events that resulted in death, functional disability or prolonged hospitalization.

The researchers say that more effective early interventions would benefit patients as well as the health care system. Currently, costs associated with the provision of atrial fibrillation-associated care are estimated at 2.5 per cent of overall annual health care expenditures. Those costs are expected to rise to four per cent within the next two decades.