Heartfailure 1s the end stage ot various heart diseases,which has ditterent underlying mechanisms but somehow has similar features among different etiologies.Dilated cardiomyopathy (DCM) and ischemic cardiomyopathy (ICM) are two major subtypes.Unlike widely explored mechanisms on these heart diseases,their shared gene expression alterations in heart failure have been rarely investigated.Methods We first obtained genetic profiles of DCM and ICM as well as their non-failing (NF) control from two datasets in GEO database,GSE3585 and GSE1869.Comparing to NF,the differentially expressed genes (DEGs) of DCM and ICM were screened out and used for Gene Ontology (GO) analysis by DAVID.The two sets of DEGs were compared and the overlap was selected out.Protein-protein interaction (PPI) network of the encoded proteins of shared DEGs was constructed and visualized via STRING and Cytoscape respectively.Gene annotation interactions were analyzed using BiNGO.The closely linked genes were sorted out as hub genes and accounted for common processes of DCM and ICM.Results There were 99 DEGs in DCM vs.NF,while 1317 DEGs in ICM vs.NF.29 DEGs were shared in two comparisons,which were mainly enriched in regulation of protein catabolic process,Golgi to endosome transport,protein targeting to Golgi,inactivation of MAPK activity,Golgi to plasma membrane protein transport,cytosol,and protein binding.There were 13 genes linked in the PPI network and thus they were selected as hub genes.Functions of these hub genes were mainly focused on energetic metabolism disorder,apoptosis and cardiac fibrosis.Conclusion Energetic metabolism disorder,apoptosis and cardiac fibrosis are likely the shared pathophysiological processes for dilated cardiomyopathy and ischemic cardiomyopathy.