Left Atrial Size and Function in a Canine Model of Chronic Atrial Fibrillation and Heart Failure.

ABSTRACT:

Background

Our aim was to assess how atrial fibrillation (AF) induction, chronicity, and RR interval irregularity affect left atrial (LA) function and size in the setting of underlying heart failure (HF), and to determine whether AF effects can be mitigated by vagal nerve stimulation (VNS).

Methods

HF was induced by 4-weeks of rapid ventricular pacing in 24 dogs. Subsequently, AF was induced and maintained by atrial pacing at 600 bpm. Dogs were randomized into control (n = 9) and VNS (n = 15) groups. In the VNS group, atrioventricular node fat pad stimulation (310 μs, 20 Hz, 3-7 mA) was delivered continuously for 6 months. LA volume and LA strain data were calculated from bi-weekly echocardiograms.

Results

RR intervals decreased with HF in both groups (p = 0.001), and

SUBMITTER: Goldberg A 

PROVIDER: S-EPMC4714887 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature