Pulmonary arterial hypertension

Pulmonary hypertension is a condition in which blood pressure in the arteries of the lungs (the pulmonary arteries) is abnormally high.

  • Many disorders can cause pulmonary hypertension.
  • People usually have shortness of breath upon exertion and loss of energy, and some people feel light-headed or fatigued on exertion.
  • Chest x-rays, electrocardiography (ECG), and echocardiography give clues to the diagnosis, but measurement of blood pressure in the right ventricle and the pulmonary artery is needed for confirmation.
  • Treatment of the cause and use of drugs that improve blood flow through the lungs are helpful.

Blood travels from the right side of the heart through the pulmonary arteries into the small blood vessels of the lungs (the capillaries) where carbon dioxide is removed from the blood and oxygen is added. Normally, the pressure in the pulmonary arteries is low, allowing the right side of the heart to be less muscular than the left side (because relatively little muscle and effort are needed to push the blood through the lungs via the pulmonary arteries). In contrast, the left side of the heart is more muscular because it has to push blood through the entire body against a much higher pressure.

If the pressure of the blood in the pulmonary arteries increases to a sufficiently high level, the condition is called pulmonary hypertension. With pulmonary hypertension, the right side of the heart must work harder to push the blood through the pulmonary arteries. Over time, the right ventricle becomes thickened and enlarged and cor pulmonale develops, resulting in right-sided heart failure.


  • Treatment of the cause of pulmonary hypertension
  • Often treatments to relieve symptoms, such as drugs that dilate blood vessels and supplemental oxygen
  • Sometimes treatments to prevent or treat complications, such as anticoagulants and lung transplantation

Treatment of pulmonary hypertension is best directed at the cause when the cause has been identified.
Vasodilators (drugs to dilate blood vessels) work by reducing blood pressure in the pulmonary arteries. Vasodilators may improve quality of life, prolong survival, and prolong the time until lung transplantation needs to be considered. Before administering vasodilators, however, doctors may first test the effectiveness of these drugs while the person is in a cardiac catheterization laboratory because use of these drugs may be dangerous in some people. Vasodilators have not proved effective for people with pulmonary hypertension due to an underlying lung disorder.

In contrast, vasodilators are often helpful for pulmonary hypertension that occurs in people with the following:

  • Idiopathic or inherited pulmonary hypertension
  • Autoimmune disorders
  • Chronic liver disease
  • HIV infection
  • Some congenital heart disorders
  • Pulmonary hypertension caused by drugs or toxins
  • Chronic thromboembolic pulmonary hypertension