"Atrial fibrillation is associated with an increased risk of stroke and cardiovascular events," said Michael Kaufmann, MD, who practices cardiology and electrophysiology at the Huntsville Hospital Heart Center and Heart Institute "So it's important to identify these patients and get them appropriate treatment."
'Appropriate treatment' continues to evolve. In June of 2021, the FDA approved cryoablation as an alternative to antiarrhythmic drug therapy as an initial strategy for symptomatic paroxysmal atrial fibrillation. Kaufmann has successfully provided care under the new guidelines.
Cryoablation, or freezing balloon, was first approved by the FDA in December 2010. Two years later, the second generation balloon was approved. Until last year, however, drug therapy was the first option for treatment, and ablation was indicated only after medication failed to address the condition.
"We offer the approach to patients," Kaufmann said. "Some still prefer to try medication first, but younger patients often opt for ablation as frontline therapy. Some patients have contraindications for heart rhythm medications. It's nice to have the option of proceeding directly with cryoablation."
Before the approval of cryoablation in 2010, Kaufmann said ablation was done using radio frequency. He estimates that nearly half of ablations performed in the country today are still radio frequency ablations, but he primarily uses cryoablation. "It's a common procedure that can be performed relatively safely," he said. "We go up through the groin, and the patient can't push, pull or lift anything heavy for a week while the groin site heals up. We keep them overnight for observation and discharge the following morning."
While both forms of ablation are efficacious, Kaufmann quotes studies that show a slightly lower rate of needing repeat ablation with cryoablation.
"Unfortunately, there is no cure for atrial fibrillation," he said. "We have treatments, and even an ablation is not a cure." Whether a patient is treated with medication or ablation, they still require monitoring and may need medication or a second ablation in the future, although cryoablation for paroxysmal atrial fibrillation has an 80 to 85 percent success rate.
There is a whole array of symptoms that might be associated with atrial fibrillation, including palpitations, fatigue, activity intolerance and shortness of breath. "Patients with atrial fibrillation who are symptomatic should be referred early," he said. "Ablations have a higher success rate if we ablate early on. Atrial fibrillation ablation success rates are not as high if patients have been in atrial fibrillation for a prolonged period of time and kind of settled in.
"The current guidelines are for symptomatic patients. There are certain circumstances where we may opt to treat patients who are asymptomatic - for instance if their heart rate is particularly fast or their heart pumping function is low - but the strongest indication for treating atrial fibrillation is symptomatic atrial fibrillation. Sometimes if patients are asymptomatic we may opt to put them on medications that will slow down their heart rate and blood thinner medicine to prevent stroke."
A large proportion of cardiac patients are on blood thinners to prevent stroke. "From a symptom standpoint, some can benefit from ablation," Kaufmann said. But ablation isn't indicated for patients who simply want to come off their blood thinner. "The way the guidelines are currently written, your need for blood thinners is based on a CHADS2VASC score. After an ablation for atrial fibrillation, if your score is still elevated, you would still need blood thinner even if the ablation appears to be successful. Those guidelines may change in the future. There are ongoing studies looking at stroke risk after successful ablation, but right now, wanting to come off blood thinner is not a reason to pursue ablation. The ablation is to reduce symptoms."
Atrial fibrillation is often thought of as a condition for older patients, but Kaufmann does see patients in their 20s and 30s. "That's uncommon. We see many fewer patients for that condition in that age group, but it can occur for a variety of reasons," he said.
That brings Kaufmann back to his original message: ablation, whether cryo or radio frequency, is most successful when done early. He urges his colleagues to refer patients of any age with symptoms before their heart has settled into atrial fibrillation for a long period, even if it is paroxysmal, or in and out.