Respiratory failure is characterized by the incapacity of the respiratory system to maintain the normal arterial blood gas homeostasis. Specifically, the overlap of hypoxaemia and hypercapnia (PaCO2 >6 kPa) is referred to as Hypercapnic Respiratory Failure (HRF). HRF is one of the most common causes for hospital admission with high re-admission rates, therefore constitute a major burden on healthcare systems. Non Invasive Ventilation (NIV) is a well established treatment in patients with hypercapnic respiratory failure who frequently suffer with associated pulmonary hypertension (PH). NIV helps to increase arterial oxygenation and reduces hypercapnia. It is used in patients with hypercapnic respiratory failure caused by Obesity Hypoventilation Syndrome (OHS). The associated degree of PH can lead to an increased afterload of the right ventricle (RV) that causes progressive remodelling of the right heart. RV dysfunction is correlated with a reduced long term prognosis in respiratory conditions. In literature NIV is shown as effective method to treat acute hypercapnic respiratory failure in OHS.