The pulmonary artery is a blood vessel which delivers deoxygenated blood to the lungs. Like all arteries, the pulmonary artery pumps blood away from the heart—in contrast to veins, which deliver blood to the heart. However, unlike most arteries, which carry blood with a relatively high oxygen content, the pulmonary artery transports blood whose oxygen content is relatively low.
The Role and Location of the Pulmonary Artery
The pulmonary artery begins in the heart at the base of the right ventricle. At this point, it is known as the pulmonary trunk, which is relatively short and wide. As it leaves the heart, the pulmonary trunk branches off in two directions –the left and right pulmonary artery. The left and right branches bring their de-oxygenated blood to the corresponding left and right lungs. There, the blood is enriched with oxygen and pumped back into our heart via the pulmonary veins. This freshly oxygenated blood flows into our heart’s left atrium, is pumped to the left ventricle, and then finally dispersed through the aorta to the arteries which carry the oxygen-rich blood throughout our body.
The pulmonary artery is one of the few arteries which transports oxygen-low blood and the pulmonary veins are among the few veins which deliver oxygen-rich blood.
How It Affects Your Health
As a major blood vessel, any vascular disease or condition which might affect smaller vessels are more severe in the pulmonary artery. One such condition which affects the pulmonary blood vessels, particularly the arteries, is pulmonary hypertension, or high blood pressure.
Pulmonary arterial hypertension is caused by, and contributes to, a narrowing, stiffening, and thickening of the arteries in and around our lungs. With diminished blood flow capacity in our arteries, our heart must work harder to pump sufficient blood to our lungs. Decreases in blood flow lead to less oxygen delivered throughout our bodies, which has a cumulative negative effect on our vascular, pulmonary, and neurological health. Therefore, pulmonary arterial hypertension is a serious cause for concern.
Risk factors for hypertension include:
- Lack of exercise
- Prolonged periods of stress
- Recreational drug use
- Advanced age
- Family history of hypertension or heart disease
Pulmonary arterial hypertension and the risk factors that lead to it also increase the likelihood of developing other conditions, such as hypertrophy of the right ventricle, pulmonary embolism, pulmonary fibrosis, and stroke.
Note that pulmonary hypertension can affect both sides of the heart. Arterial hypertension affects the right side; it relates to poor vascular health in the arteries in and around the lungs. Hypertension on the left side of our heart relates less to blood vessels, and more to the failure of the heart’s left chambers to pump blood efficiently. This can lead to other conditions, such as a pooling of blood in the lungs, pulmonary edema, and pleural effusions. However, pulmonary hypertension on either side of our heart has the same risk factors. Therefore, if the risk factors characterize you, lifestyle changes can lead to corresponding improvements in our health.