Transcriptional changes associated with advancing stages of heart failure underlie atrial and ventricular arrhythmogenesis

Heart failure (HF) is a leading cause of mortality and is associated with cardiac remodeling. Vulnerability to atrial fibrillation (AF) has been shown to be greater in the early stages of HF, whereas ventricular tachycardia/fibrillation develop during late stages. Here, we explore changes in gene expression that underlie the differential development of fibrosis and structural alterations that predispose to atrial and ventricular arrhythmias. To study transcriptomic changes associated with the development of cardiac arrhythmias in early and late stages of heart failure. Dogs were tachy-paced from right ventricle (RV) for 2-3 or 5-6 weeks (early and late HF). We performed transcriptomic analysis of right atria (RA) and RV isolated from control dogs and those in early and late HF. Transcripts with mean relative log2-fold change ≥2 were included in the differential analysis with significance threshold adjusted to p