The prevalence rates for atrial fibrillation (AF) are increasing, and annual costs to treat this disease are estimated to be $7 billion. Our research at the University of Utah has shown significant and promising results in applying late gadolinium-enhanced (delayed enhancement) cardiac MRI (DE-MRI) technology for non-invasive scar assessment in the left atrium (LA). For example, used prior to catheter ablation, DE-MRI can identify regions of significant structural remodeling or fibrosis. This imaging modality has also been shown to be very useful in examining the amount and distribution of ablation-related scarring.

Because DE-MRI effectively demonstrates the degree of LA tissue fibrosis and tissue injury — both pre- and post-ablation — our research indicates that it is possible to stage the progression of AF based on the amount of pre-ablation fibrosis. Beginning this summer, a new, international multi-site study will further expand our experience with DE-MRI image acquisition and its applications in the management of AF.

Sixteen renowned medical centers are expected to begin enrolling patients in the University of Utah’s Determinant of Successful Radiofrequency Catheter Ablation of Atrial Fibrillation (DECAAF) study, including the Mayo Clinic, the Cleveland Clinic and universities in Germany, France, the Netherlands, Belgium and Australia. Its three specific aims are to:

• Acquire DE-MRI scans of the left atrium in AF patients and quantify the extent of structural remodeling or fibrosis.
• Acquire DE-MRI scans of the left atrium three months post-catheter ablation, quantify the extent of ablation-related scarring, and describe its distribution.
• Evaluate the relative contribution of clinical patient characteristics, pre-ablation fibrosis and post-ablation scarring in determining the long-term success of catheter ablation in maintaining normal rhythm.

As part of the study, we will develop image processing and visualization methods that will help maximize the reproducibility of the techniques. This research will greatly increase our understanding of the process of LA remodeling after treatment of AF with ablation. One of its primary goals is to establish the use of DE-MRI to stage AF and predict outcomes prior to AF ablation procedures.

For more information about the DECAAF study, contact Corinne Garcia, our Clinical Research Manager, at cgarcia@sci.utah.edu.

Nassir F. Marrouche, MD is the Executive Director of the Comprehensive Arrhythmia Research & Management Center, Director of Electrophysiology Laboratories, and Director of the Atrial Fibrillation Program at the University of Utah School of Medicine, Division of Cardiology.