AGTR1 and hydrops fetalis: Indeed, a compound analogous to SII, i.e., a βarr-”biased” AT1R peptide agonist that selectively activates βarrs while blocking G-protein signaling, TRV120027, has shown very promising results in canine models of acute HF, blocking the undesirable G protein-mediated AT1R-induced vasoconstriction, thereby preserving renal function, while, at the same time, enhancing the desirable (in acute HF) βarr-dependent contractility of cardiac myocytes [55], and it is currently under development for the treatment of HF.