In the human heart, the pulmonary trunk ('pulmonary artery or main pulmonary artery) begins at the base of the right ventricle. It is short and wide—approximately 5 centimetres (2.0 in) in length and 3 centimetres (1.2 in) in diameter. It then branches into two pulmonary arteries (left and right), which deliver deoxygenated blood to the corresponding lung.oo
The pulmonary artery pressure is a measure of the blood pressure found in the pulmonary artery. This is measured by inserting a catheter into the pulmonary artery.:190-191 The mean pressure is typically 9 - 18 mmHg., and the wedge pressure measured in the left atrium may be 6-12mmHg. The wedge pressure may be elevated in left heart failure:190-191 and other conditions, such as sickle cell disease.
The pulmonary artery is relevant in a number of clinical states. Pulmonary hypertension is used to describe an increase in the pressure of the pulmonary artery, and may be defined as a mean pulmonary artery pressure of greater than 25mmHg.:720 This may occur as a result of heart problems such as heart failure, lung or airway disease such as COPD or scleroderma, or thromboembolic disease such as pulmonary embolism or emboli seen in sickle cell anaemia.:720-721