Aims: Adaptation of the right ventricle (RV) to increased afterload is crucial for survival in pulmonary hypertension (PH), but it is challenging to assess RV function and identify associated molecular mechanisms. Aim of the current study was to analyze the relationship between invasive and non-invasive parameters of RV morphology and function and associated molecular changes. Methods: The response of mice to normobaric hypoxia was assessed by echocardiography, invasive hemodynamics, histology and molecular analysis. Plasma levels of possibly novel markers of RV remodeling were measured by ELISA in patients with idiopathic pulmonary arterial hypertension (IPAH) and matched healthy controls. Results: Chronic hypoxia-induced PH was accompanied by significantly decreased tricuspid annular plane systolic excursion (TAPSE) and unchanged RV contractility index and tau. RV hypertrophy was present without an increase in fibrosis. There was no change in α- and β-MHC or natriuretic peptides expression. Comparative microarray analysis identified two soluble factors, FGF5 and IL22RA2, as possibly associated with RV remodeling. We observed significantly increased plasma levels of IL22RA2, but not FGF5, in IPAH patients. Conclusions: Hypoxic pulmonary hypertension in a stage of RV remodeling with preserved systolic function is associated with decreased pulmonary vascular compliance, mild diastolic RV dysfunction and significant decrease in TAPSE. Subtle gene expression changes in the RV versus LV upon chronic hypoxia suggest that the majority of changes are due to hypoxia and not due to changes in afterload. Increased IL22RA2 levels might represent a novel RV adaptive mechanism.