In this study, we report novel discoveries that establish the in vivo functional relationship between β1AR/β-arrestin signaling selectively in CMs and miR-150 in HF, delineate the functional Gm41664/miR-150 link in CM apoptosis, as well as identify a new direct and functional target of miR-150, Gdap1l1 in CMs. This evidence concerns the gene GDAP1L1 and hydrops fetalis.