A new study shows catheter ablation, a common procedure used to treat heart rhythm disorders, may reduce stroke risk for those with atrial fibrillation (AF) - the most common arrhythmia. The multicenter study, published in the September edition of HeartRhythm, the official journal of the Heart Rhythm Society (HRS), is the first to show AF ablation patients have significantly lower risk of stroke compared to AF patients who do not undergo ablation regardless of stroke risk profile.

The study included a total of 37,908 patients representing three different groups: patients with AF who had undergone ablation (4,212), patients with AF who did not undergo ablation (16,848), and patients without a history of AF (16,848). Patients were enrolled from the large, ongoing Intermountain Atrial Fibrillation Study Registry and were followed for at least three years. The patients were matched according to the CHADS2 risk profile, which is based on risk according to congestive heart failure, hypertension, age, diabetes, and stroke symptoms.

Across all risk profiles and ages, AF patients with ablation had a lower long-term risk of stroke compared to patients without ablation. There was a significantly higher rate in those patients with AF who did not undergo ablation (590 patients,) compared to those with AF who underwent ablation (61 patients) and those with no history of AF (242 patients).

"For the first time, this large study shows us that catheter ablation favorably impacts stroke risk in all patients that have atrial fibrillation and undergo the procedure regardless of their existing stroke risk profile," stated lead-author T. Jared Bunch, MD, Intermountain Medical Center. "These results are encouraging because it provides us with data regarding the type and quality of care and treatment outcomes in patients who live with AF - a very common, yet very treatable condition."

What is AF and who's affected?

AF is characterized by a rapid and irregular heartbeat caused when the top chambers of the heart (the atria) quiver (fibrillate) erratically, sometimes faster than 200 times per minute. The condition can have a significant negative impact on an individual's quality of life, causing heart palpitations, chronic fatigue and debilitating pain. An estimated 3 million adults in the United States (U.S.) have been diagnosed with AF. As the world population ages, the prevalence of AF is projected to increase. In fact, in the next 30-40 years, the number of people diagnosed with AF in the U.S. is expected to more than double.

"A survey conducted earlier this year by HRS showed that 1 in 4 Americans between the ages of 55 and 64 had never heard of AF. Low levels of AF awareness are discouraging because it is one of the more common arrhythmias we treat," said Hugh Calkins, MD, FHRS, president of Heart Rhythm Society. "It is through great work such as this study led by Dr. Bunch, along with public awareness initiatives like our annual 'AFib Feels Like' campaign, that we can work to increase knowledge about AF and its related risks, such as stroke."

How is AF connected to stroke risk?

People with AF are five times more likely to have a stroke compared to people without the condition and it is estimated that AF accounts for 15 percent of all strokes. To reduce this higher risk of stroke, doctors often prescribe blood thinners (anticoagulants) to AF patients. Over the past decade, catheter ablation has emerged as an alternative therapy for treating AF, and is now a widely performed ablation procedure worldwide.[1]

For more information, visit the HRS AF Fact Sheet