Pulmonary hypertension is characterized by a mediator imbalance with a predominance of vasoconstriction and cell proliferation involving all layers of the vessel. The end result is an increase in pulmonary vascular resistance, increased workload of the right ventricle, and right ventricular hypertrophy to maintain an adequate flow. Subsequently, right ventricular dilatation ensues the signs and symptoms of right heart failure occurence. Therefore, while the origin of the anatomical disturbance is at the level of the pulmonary arteries resistance, the end result is right heart failure
