Denver, CO - The strategy is widely used and seems to make a difference in the realms of heart failure and hypertension, and lately it's being tried in atrial fibrillation (AF), with what seems to be—at one institution, anyway—promising and sometimes surprising results.

Three fourths of patients referred over two years to a tertiary-center-based dedicated "atrial fibrillation center" for management of their arrhythmia had their ongoing treatment adjusted or changed entirely, with significant associated reductions in symptomatic-AF duration and frequency, according to a report here at the Heart Rhythm Society 2007 Scientific Sessions [1].

Liza A Prudente

Sometimes the treatment change was fundamental, such as catheter ablation for a patient poorly managed on drugs, observed Liza A Prudente (University of Virginia, Charlottesville), who presented the findings. Other times it was only a slight adjustment. "Often they'll come to us on a drug regimen that's reasonable but the dosage isn't quite right," she told heartwire. "Modifying the existing regimen is often sufficient to decrease their symptom burden."

Prudente is an acute-care nurse practitioner at her institution's atrial fibrillation center, which was founded in 2004. A number of other large, often-university-affiliated medical centers around the US have established similar specialized departments for treating and following patients with AF, just as they have for heart failure and some other conditions, but there aren't much data on whether the strategy is accomplishing its various intended goals. They can include not only improved clinical outcomes for patients but also a bigger bottom line from increased referrals for the institution.

One noteworthy finding in her group's data, according to Prudente, is that patients had significantly fewer symptoms after referral to the center regardless of whether their ongoing management was altered. What seemed to make the difference, she said, was the more personal, consistent, and clinically attentive care they were getting compared with how they were managed before. "We like to think that what we do for patients in terms of treating their atrial fibrillation is what decreases their AF burden, but in fact I think it's that we provide them with additional education, we tweak their other medications, and we address other medical issues going on with them," she said.

Dr Jack Kron (Source: Oregon Health & Science University)

Dr Jack Kron (Oregon Health & Science University, Portland), who isn't connected with Prudente's study, said that dedicated AF clinics can often reduce patients' burden of AF by finding and treating underlying conditions that had escaped the notice of referring physicians. For example, he told heartwire, a sleep study may disclose sleep apnea syndrome as a possible contributor to AF. Often, treatment of the sleep apnea will, on its own, improve the burden of AF symptoms, he said. Kron is director of electrophysiology in the cardiovascular division at his center.

The atrial fibrillation center at the University of Virginia opened its doors in October 2004 and is gaining new patients at the rate of more than 400 per year, according to Prudente. The rate of follow-up visits to the center has been increasing and currently exceeds 1000 per year. The referrals have come from a spectrum of practitioners, from primary-care physicians to general cardiologists and cardiac electrophysiology specialists, all with differing levels of training and expertise in managing AF. Some may not be up-to-date on evidenced-based drug therapy of AF; others may not know that catheter ablation is now an accepted second-line therapy, she said. "We make sure that the patients know all the options available to them."

During the first two years of its operation, 1045 patients were referred to the center, of whom 53% had already been on at least one antiarrhythmic drug, Prudente reported. Their mean symptomatic AF burden, defined as their proportion of time spent in AF derived from estimated symptom duration and frequency, was 39%.

After an initial evaluation, about 65% of the patients were managed with rhythm-control therapies such as antiarrhythmic drugs, cardioversion, or catheter ablation. Rhythm control was most likely to be used in younger patients and those with symptoms of longer duration. Most of the remaining patients received pacemakers or drug- or catheter-based treatments for rate control. Importantly, Prudente reported, 76% of the patients had changes made to the treatments they were on at the time of referral.

In the 527 patients with available six-month outcomes data, the symptomatic AF burden fell from 35% at the time of referral to 14% at the follow-up for patients managed with rhythm control and 15% for those who received rate-control therapies (p<0.0001 for both differences). Most of the improvement in symptom burden occurred right after the initial evaluation and was maintained in the ensuing months. The decreases were significant regardless of whether a change had been made to patients' management.

Prudente said that about 20% of the center's patients who underwent catheter ablation for their AF subsequently developed recurrences, either silent or symptomatic. But the rate of symptomatic recurrence was much lower—patients generally felt significantly better after the procedure. "Even though they may have had recurrences, they tended to be far less often or of shorter duration than what they were accustomed to."