Patients with atrial fibrillation often must take blood thinners for life in order to avoid blood clots and strokes. Treatment options for atrial fibrillation have been limited to medications such as blood thinners, which may normalize rhythm, but research has shown that these medications have low efficacy.

The seminal observation by Michel Haissaguerre, MD and colleagues found that arrhythmogenic foci within the pulmonary veins could trigger atrial fibrillation. At the University of Michigan, radiofrequency (RF) energy catheter ablation has been used to treat patients with atrial fibrillation in clinical settings and the preliminary results have been positive. Initially, segmental ostial ablation was performed to electrically isolate the RF catheter ablation so as to counteract irregular electrical impulses in the heart muscle by delivering tiny bursts of RF waves to the areas of disorganized activity.

With this approach, we were able to achieve a long-term efficacy of approximately 65% to 70% and patients had a reduced need for medications. Another approach has been circumferential ablation in the left atrium to encircle the left- and right-sided pulmonary veins with additional lines in the posterior left atrium and along the mitral isthmus.

In a recent randomized study, Fred Morady, MD and I compared the efficacy of segmental ostial ablation (SOA) and left atrial circumferential ablation (LACA) in 80 patients with paroxysmal atrial fibrillation. Both approaches could be performed within 2.5 hours and the risk of complications was low. These results were encouraging and RF ablation for atrial fibrillation will continue to evolve.

At present, the procedures are performed only in high-volume specialized centers, but it could become useful in more hospital settings. As more physicians learn the intricacies of the procedure, it will become more prevalent. The procedure by itself is not extremely complicated and can be performed after a short learning curve. While it requires some technical expertise, there are efforts to simplify the procedure so that it can be performed by more physicians across the country.

REFERENCE LINKS:

Society of Interventional Radiology www.sirweb.org/patPub/radiofrequencyAblation.shtml