Cor pulmonale is a heart condition in which the right ventricle cannot pump blood to the lungs due to hypertrophy (enlargement) of the right side caused by prolonged high blood pressure in the pulmonary arteries. This incapability of the right ventricle to pump enough blood to the lungs is called right side failure. If it is not treated, cor pulmonale can lead to death. In cor pulmonale the right ventricle is not capable of pumping enough blood because of these abnormally high blood pressures in the arteries of the lungs, called pulmonary hypertension. Almost any chronic lung disease or condition causing prolonged low blood oxygen levels can lead to cor pulmonale.
The heart has two pumping chambers called ventricles. The left ventricle pumps blood throughout the body. The right ventricle pumps blood to the lungs where it is oxygenated and returned to the left ventricle of heart for distribution. In normal circumstances, the right heart pumps blood into the lungs without any resistance. The lungs usually have minimal pressure and the right ventricle easily pumps blood to the lungs. When a lung disease occurs, like emphysema, chronic obstructive lung disease (COPD) or pulmonary hypertension- the small blood vessels become very stiff and rigid. The right ventricle is no longer able to push blood into the lungs and eventually fails. This is known as right heart failure or cor pulmonale. Thus, the chief cause of right heart failure is the increase in blood pressure in the lungs (pulmonary artery).