One of the main reasons for respiratory failure complicating right heart failure is that the cardiopulmonary cycle, the right ventricular arterial blood to the pulmonary artery, the pulmonary artery blood in the alveoli with oxygen into the pulmonary vein, the pulmonary vein blood and then into the left atrium, if respiratory failure occurs, the resistance of the pulmonary circulation increases, and the load resistance of the right heart also increases, and often the formation of heart failure. Lead to the right heart failure is mainly the following reasons: 1, pulmonary hypertension, because there are many factors in the pulmonary circulation leads to increased pulmonary artery pressure, at the same time due to hypoxia leads to myocardial damage, the heart itself factors are also damaged; 2, respiratory failure, leading to an increase in blood viscosity, increasing myocardial oxygen consumption. These factors lead to poor function of the heart and lungs, such as increased pulmonary resistance, increased work done by the heart, the myocardium is increased damage, eventually leading to right heart failure.