Cryoablation may be a Better First-stage Atrial Fibrillation Treatment
A recent study comparing atrial fibrillation (AF) treatments, published in The New England Journal of Medicine, shows that early intervention with cryoballoon catheter ablation (cryoablation) is more effective at reducing the risk of serious long-term health impacts, when compared to the current first step in treatment, antiarrhythmic drugs.
“By treating patients with cryoablation right from the start, we see fewer people advancing to persistent, more life-threatening forms of atrial fibrillation,” says Dr Jason Andrade, an associate professor of medicine at University of British Columbia. “In the short term, this can mean less recurrences of arrhythmia, improved quality of life and fewer visits to the hospital. In the long run, this can translate into a reduced risk of stroke and other serious heart problems.”
When used for AF, cryoablation is a minimally invasive procedure that involves guiding a small tube into the heart to kill problematic tissue by freezing. Historically, the procedure has been reserved as a secondary treatment when patients don’t respond to antiarrhythmic drugs.
“This study adds to the growing body of evidence that early intervention with cryoablation may be a more effective initial therapy in the appropriate patients,” says Dr Andrade.
Early intervention halts disease progression
AF affects approximately 3% of the population, and 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 persistent AF, where episodes last more than seven days.
“Atrial fibrillation is like a snowball rolling down a hill. With each atrial fibrillation episode there are progressive changes in the heart, and the heart rhythm problem gets worse,” explains Dr Andrade.
The new findings, stemming from a multi-site clinical trial, show that cryoablation can stop this snowball effect.
Researchers enrolled 303 patients with AF in Canada. Half of the patients were randomised 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.
At three years follow-up, 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 hospitalisation rates and experienced fewer serious adverse health events that resulted in death, functional disability or prolonged hospitalisation.
Addressing the root cause
Because cryoablation targets and destroys the cells that initiate and perpetuate AF, the researchers say it can lead to longer-lasting benefits.
“With cryoablation, we’re treating the cause of the condition, instead of using medications to cover-up the symptoms,” says Dr Andrade. “If we start with cryoablation, we may be able to fix atrial fibrillation early in its course.”
The new study builds on previous work by Dr Andrade and colleagues demonstrating that cryoablation was more effective than antiarrhythmic drugs at reducing the short-term recurrence of atrial fibrillation.
