Right atrial appendages were obtained from 30 patients undergoing open heart surgery for valve repair or coronary artery bypass grafting. Of these, ten patients had permanent AF defined as duration of AF longer than three months as documented by ECG, and 20 patients had no history of AF and were in sinus rhythm when open heart surgery was performed. Transmural LV tissue was obtained from five non-failing donor hearts which were not transplanted due to palpable coronary calcifications. After excision, all tissue specimens were immediately frozen in liquid nitrogen and stored at -80°C. Total RNA was purified from homogenized deep-frozen tissue samples following the TRIZOL standard protocol as described by the manufacturer (GibcoBRL, Eggenstein, Germany) and quantified by photometry. 150ng total RNA was used for quality control using the RNA 6000 Nano LabChip kit and Agilent Bioanalyzer 2100 (Agilent Technologies, Palo Alto, CA, USA). Synthesis of double-stranded cDNA and of biotinylated cRNA probes as well as subsequent steps of hybridization, washing, and staining followed instructions provided by Affymetrix (Affymetrix, Santa Clara, CA, USA). One set of U133A+B chips (together representing 44.928 probe sets) was used for each human heart sample. All U133 GeneChips passed quality control to eliminate scans with abnormal characteristics, i.e. abnormal low or high dynamic range, high perfect match saturation, high pixel noise, grid misalignment problems, and low mean signal to noise ratio. Low level and statistical analysis was done using R 1.8.1. Microarray data of all atrial and ventricular samples was normalized simultaneously using robust multi-array average (RMA) implemented in Bioconductor's "affy"-package. Keywords = Homo sapiens, myocardial tissue, comparison of right atrial tissue of patients with atrial fibrillation and sinus rhythm with left ventricular gene expression
Comparison of atrial tissue of patients with atrial fibrillation and sinus rhythm with ventricular gene expression
Data table header descriptions
ID_REF
Affymetrix probe set ID
VALUE
'signal' a measure of the abundance of a transcript (after normalization with robust-multiarray average (RMA) implemented in Bioconductor's affy-package)
ABS_CALL
the call in an absolute analysis that indicates if the transcript was present (P), absent (A), or marginal (M).
DETECTION P-VALUE
'detection p-value', p-value that indicates the significance level of the detection call, as calculated by the Bioconductor's affy-package.