Progression of heart failure induced by tachycardia

Analysis of changes of gene expression profiles in the left ventricle (LV) during the progression of heart failure (HF) in the canine tachypacing induced HF model. Gene expression profiling was performed on samples collected at different time points representing various stages of LV dysfunction, i.e. tachypaced for 3 days (Day-3), 1 week (Week-1), 2 weeks (Week-2), 3-4 weeks (End stage), and unpaced controls (Day-0). Results provide insights into molecular mechanisms of heart failure progression. Keywords: time course This work aims to study changes of gene expression profiles in the left ventricle (LV) during the progression of heart failure (HF) in the canine tachypacing induced HF model. LV transmural tissue sections were collected at different time points after initiating rapid pacing representing various stages of LV dysfunction, i.e. tachypaced for 3 days (Day-3), 1 week (Week-1), 2 weeks (Week-2), 3-4 weeks (End stage), and unpaced controls (Day-0). As biological replicates, tissues were collected separately from 3 individual dogs at each of the time points. In total we collected 15 tissue samples for all 5 time points. Three RNA samples were independently isolated from each of the 15 tissue samples as technical replicates. The resulting 45 RNA samples were used for microarray experiment. Affymetrix gene expression profiles of the 45 RNA samples were used for all data analysis in this study.