Fig. 503 - Transverse section of
Thorax , showing relations of
Pulmonary Artery .]]
The carry
Blood from the
Heart to the
Lungs . They are the only
Arteries (other than
Umbilical Arteries in the fetus) that carry deoxygenated blood.
In the human
Heart , the ('''pulmonary artery''' or '''main pulmonary artery''') begins at the base of the
Right Ventricle . It is short and wide - approximately 5 cm (2 inches) in length and 3 cm (1.2 inches) in diameter. It then branches into two pulmonary arteries (left and right), which deliver deoxygenated blood to the corresponding
Lung .
Pulmonary Hypertension occurs alone and as a consequence of a number of
Lung Diseases . It can be a consequence of
Heart Disease (
Eisenmenger's Syndrome ) but equally a cause (right-ventricular
Heart Failure ); it also occurs as a consequence of
Pulmonary Embolism and
Scleroderma . It is characterised by reduced exercise tolerance. Severe forms, generally, have a dismal prognosis.
