Abstract
Studies about pulmonary hypertension and congenital heart diseases have introduced the concept of right ventricular remodeling leading these pathologies to a similar outcome: right ventricular failure. However right ventricular remodeling is also a physiological process that enables the normal fetal right ventricle to adapt at birth and gain its adult phenotype. The healthy mature right ventricle is exposed to low pulmonary vascular resistances and is compliant. However, in the setting of chronic pressure overload, as in pulmonary hypertension, or volume overload, as in congenital heart diseases, the right ventricle reverts back to a fetal phenotype to sustain its function. Mechanisms include angiogenic changes and concomitant increased metabolic activity to maintain energy production. Eventually, the remodeled right ventricle cannot resist the increased afterload, leading to right ventricular failure. After comparing the fetal and adult healthy right ventricles, we sought to review the main metabolic and cellular changes occurring in the setting of PH and CHD. Their association with RV function and potential impact on clinical practice will also be discussed.