RLN2 and pulmonary arterial hypertension: The concept of this compensatory increase in the hormone relaxin-2 in response to PAH and RV anomalies was also supported by clinical trials in which serelaxin administration to AHF patients induced a vasodilator effect on the pulmonary vessels, causing a notable decrease in pulmonary capillary wedge pressure (PCWP), PAP, PVR, and right atrial (RA) pressure [156].