MINNEAPOLIS and SAN FRANCISCO – Medtronic, Inc. today announced findings from the DISCERN AF trial, which utilized Medtronic’s Reveal® XT insertable cardiac monitor to conduct long-term monitoring to assess the incidence of symptomatic versus asymptomatic atrial fibrillation (AF) episodes in patients before and after undergoing radiofrequency (RF) ablation as compared to the AF status reported prior to the procedure. The clinical trial showed an 86 percent reduction in total AF burden (total amount of time spent in atrial fibrillation) from 2.0±0.5 hours per day per patient pre-ablation to 0.3±0.2 hours per day per patient post- ablation (p=0.005), with 56 percent of the total burden being asymptomatic.

The investigator-initiated study, which was supported by Medtronic and presented today as a late-breaking clinical trial at Heart Rhythm 2011, the Heart Rhythm Society’s 32nd Annual Scientific Sessions, also showed the ratio of asymptomatic to symptomatic AF increased post-RF ablation. When analyzing symptoms alone, 58 percent of patients were free of AF according to Reveal XT monitoring. This finding suggests that symptoms clearly underestimate overall disease burden post-ablation, since 12 percent of patients in the trial had only asymptomatic AF recurrence as documented by Reveal XT.

“These study findings are promising and fulfill a significant unmet need in the cardiac clinical community when it comes to determining asymptomatic AF in patients who are defined as ‘cured’ based on symptoms,” said Atul Verma, M.D., principal investigator and electrophysiologist, Southlake Regional Health Centre, Newmarket, Ontario, Canada. “Given the incidence of asymptomatic AF before and after RF ablation, a better understanding of the true AF burden may help physicians in their long-term management of this patient population.”

RF ablation is considered an effective treatment method for atrial fibrillation. Patients currently indicated for this procedure have highly symptomatic AF that is resistant to drug therapy. However, the overall incidence of asymptomatic AF episodes post-ablation is unclear. Determining the occurrence of asymptomatic AF episodes may be important to ensure patient safety, as the disease can lead to a significantly higher risk of stroke and an increased risk of heart failure. The Reveal family of devices offers varying capabilities and information to physicians seeking to diagnose patients with suspected arrhythmias, and to monitor patients with AF to help make disease management decisions.

“This study underscores the value of Reveal in providing solid clinical insight into the progression of AF and the effect of ablation treatment, which can help guide AF patient care,” said Pat Mackin, president of the Cardiac Rhythm Disease Management business and senior vice president at Medtronic. “Medtronic is committed to developing leading medical technologies to treat and manage cardiac rhythm diseases such as AF, and new research such as DISCERN AF is a cornerstone to guide our development strategies.”

Source: Medtronic, Inc.