Ablation stopped atrial fibrillation in 81% of patients in new study

Radiofrequency (RF) ablation is the most common treatment for atrial fibrillation (AFib), an irregular and usually fast heartbeat.

Research shows that the procedure is safe and effective, but over the years, clinicians have refined RF ablation to improve its safety and effectiveness.

Despite its widespread use, few studies have examined how modifications and improvements in RF ablation techniques have affected its effectiveness.

A recent study published in the journal Heart Rhythm examined the success of RF ablation at several large hospitals in the United States. The researchers found that one year after RF ablation, 81.6% of patients were free of atrial fibrillation. Of those patients, 89.7% were able to stop taking medications to treat the condition.

These figures are higher than those achieved in clinical trials, showing that the modifications have indeed improved safety and efficacy.

Atrial Fibrillation and RF Ablation

Atrial fibrillation (AFib) is the most common form of arrhythmia, an abnormal heart rhythm. In Australia, the United States and Europe, it affects 1–4% of the population and is particularly common among older people.

By disrupting blood flow, causing palpitations, shortness of breath, and chest pain, AFib increases the risk of other problems.

Dr. Paul Drury, a board-certified cardiologist who was not involved in the study, said:

"Atrial fibrillation, although not considered a life-threatening condition, is a serious health problem, increasing a patient's lifelong risk of stroke and congestive heart failure. It often requires lifelong monitoring and treatment."

Drury is associate medical director of electrophysiology at MemorialCare Saddleback Medical Center in Laguna Hills, California.

RF ablation is a common treatment for AFib. It uses heat to destroy areas of heart tissue that cause the condition. The technique has been used for years, most often to treat gastrointestinal problems.

Re-evaluation of RF ablation for the treatment of AFib

Early randomized controlled clinical trials showed that early versions of RF ablation had good safety and efficacy.

However, over time, clinicians have gradually refined the procedure's techniques, so it's unclear how effective these new methods are in real-world settings. In addition, few real-world studies have examined the procedure outside of early clinical trials.

A recent study helps fill this gap in our understanding. The authors presented their findings at the Heart Rhythm 2024 conference in Boston, Massachusetts.

Dr. Paul S. Zey, MD, of Brigham and Women's Hospital in Boston, Massachusetts, is one of the authors of the new study.

Zei explained that he and his colleagues "believed that if a group of experienced electrophysiologists in a real-world setting could come together and collect data to evaluate detailed procedural practices, including innovations that group members had implemented into their standard practice, this might be a way to create real-world evidence that could improve procedural outcomes."

Zei and his team analyzed data from a registry called the Real-World Experience with Catheter Ablation for the Treatment of Symptomatic Paroxysmal and Persistent Atrial Fibrillation (REAL-AF) registry.

This multidisciplinary registry was founded in 2019 by Zei and colleagues. Comprising 50 medical centers, it is designed to assess long-term outcomes in patients treated for AFib.

It is important to note that all of these medical centers regularly perform RF ablation procedures and use new advanced techniques such as:

• targeting the pulmonary vein, the area where AFib often begins;
• Minimizing fluoroscopy during the procedure - this reduces radiation exposure;
• using shorter, more powerful radiofrequency pulses to speed up the procedure.

Analysis of results

Scientists analyzed data from 2,470 patients with AFib treated with RF ablation to create the REAL-AF registry.

All participants had paroxysmal atrial fibrillation, a form of AFib in which symptoms come and go over time. The researchers focused particularly on the techniques used and the timing of the procedure.

They assessed the patients' results immediately after the procedure and one year later.

"We studied experienced operators and centers to try to make sure that we were learning the best techniques that were already being used," Zei explained. "Our motivation is to learn the best approaches to RF ablation and adapt and improve those approaches so that our results become even better."

Data from the REAL-AF registry showed that RF ablation procedures were more effective, efficient, and safe than data from randomized clinical trials. This is quite a surprising finding.

"Generally, real-world registries show less effectiveness than many randomized trials," noted Shephal Doshi, MD, a board-certified cardiac electrophysiologist.

Doshi explained that this is because "in clinical practice, physicians may not follow protocols or study techniques and may get suboptimal results. In this example, this registry showed even better results with improvements in RF ablation procedures, which is not common and shows the power of a learning healthcare network."

Doshi, who was not involved in the study, is director of cardiac electrophysiology and pacing at Providence Saint John's Health Center in Santa Monica, California.

One year after the procedures, 81.6% of participants were free of atrial arrhythmia.

Importantly, the vast majority – 93.2% – were free of arrhythmia symptoms for 12 months after the procedure.

The scientists also found that the average procedure time was significantly shorter, meaning patients need to spend less time under anesthesia, which is safer and frees up clinicians' time to perform more procedures.

The authors conclude that refinements to RF ablation for the treatment of paroxysmal AFib "have resulted in excellent short-term and long-term clinical outcomes."

A Look into the Future of AFib Treatment

The authors plan to expand their research to examine other forms of AFib, including persistent AFib, which is more difficult to treat.

"The goal is to spread best practices to every operator and center," Zei explained.

Zei said he and his team will continue to collect and analyze data using the REAL-AF registry.

"As this registry gets larger and more data is collected, we are reaching a point where we can now use this network of physicians as a learning health network where data generation, clinical implementation and outcome improvement can be continuously implemented."

New techniques are also being developed, including so-called pulsed field ablation, which uses electrical fields instead of heat to destroy heart tissue.

RF ablation is still the most common technique today, so continuous improvement of the procedure is important. Additionally, Zei and his team "plan to evaluate pulsed field ablation as participants gradually adopt these platforms."