Downstream effector of Notch signaling which may be required for cardiovascular development. Transcriptional repressor which binds preferentially to the canonical E box sequence 5'-CACGTG-3'. Represses transcription by the cardiac transcriptional activators GATA4 and GATA6. {ECO:0000269|PubMed:10692439, ECO:0000269|PubMed:11095750, ECO:0000269|PubMed:15485867, ECO:0000269|PubMed:16293227}. This is the function of HEY2 (hes related family bHLH transcription factor with YRPW motif 2, Ensembl gene identifier ENSG00000135547).