Dr. Arnar also presented preliminary results from an ongoing brain perfusion imaging study conducted in AF patients before and after direct current cardioversion. Among 17 patients who responded to cardioversion by going into sinus rhythm and staying there for at least 10 weeks until their follow-up MRI, total cerebral blood flow improved by a mean of 70 mL/min from a precardioversion figure of 557 mL/min. Both white and gray matter perfusion improved by a mean of 16%.
In contrast, the 10 patients who remained in AF despite the cardioversion attempt showed no improvement in any of these three endpoints over the 10 weeks.
Audience members wondered whether being on warfarin or beta blocker therapy affected the rate of brain volume loss or cognitive function. Not in the cross-sectional study published in Stroke, Dr. Arnar replied. However, those analyses have yet to be conducted in the new longitudinal study.
The AGES-Reykjavik Study is funded by the U.S. National Institutes of Health, Icelandic Heart Association, and the Icelandic Parliament. Dr. Arnar reported having no financial conflicts.