Contribution of fibrosis and the autonomic nervous system to atrial fibrillation electrograms in heart failure.

ABSTRACT:

Background

Fibrotic and autonomic remodeling in heart failure (HF) increase vulnerability to atrial fibrillation (AF). Because AF electrograms (EGMs) are thought to reflect the underlying structural substrate, we sought to (1) determine the differences in AF EGMs in normal versus HF atria and (2) assess how fibrosis and nerve-rich fat contribute to AF EGM characteristics in HF.

Methods and results

AF was induced in 20 normal dogs by vagal stimulation and in 21 HF dogs (subjected to 3 weeks of rapid ventricular pacing at 240 beats per minute). AF EGMs were analyzed for dominant frequency (DF), organization index, fractionation intervals (FIs), and Shannon entropy. In 8 HF dogs, AF EGM correlation with underlying fibrosis/fat/nerves was assessed. In HF compared with normal dog

SUBMITTER: Koduri H 

PROVIDER: S-EPMC3607299 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature