Pulmonary hypertension (PH) is a lung disorder in which the blood pressure in the pulmonary arteries rises above normal levels.

There are many causes of pulmonary hypertension.

Known causes include:

  • Vascular diseases such as scleroderma, lupus or Crest syndrome
  • Congenital heart diseases such as ventricular and atrial septal defects
  • HIV infection
  • Liver disease

The increased pressure causes your body to have to work harder to pump blood through the lungs, and as a result, the right side of the heart becomes enlarged. As the disease progresses, right heart failure may develop.

There are several types of Pulmonary Hypertension:

  • Pulmonary arterial hypertension (PAH): This is a condition where the arteries that supply blood to the lungs become narrow. This increases the resistance to blood flow, resulting in higher lung pressures. 
  • Pulmonary Hypertension Due to Left Heart Disease: A condition where disorders of the left side of the heart, such as left heart failure, heart stiffening and valvular heart disease can result in PH.
  • Pulmonary Hypertension Due to Lung Disease: This is a condition where diseases that affect the lung tissue result in pressure elevation. These include obstructive sleep apnea, chronic obstructive pulmonary disease, and interstitial lung disease.
  • Chronic Thromboembolic Pulmonary Hypertension (CTEPH): This is a condition where blood clots result in narrowing of the pulmonary arteries. If the blood clots do not fully dissolve, they can cause PH.
  • Idiopathic Pulmonary Arterial Hypertension: When pulmonary hypertension occurs without a known cause, it is called idiopathic pulmonary arterial hypertension (IPAH). This means that there are no other diseases of the heart or lungs causing the high blood pressure. Some cases are inherited, called familial PAH.
  • Miscellaneous: This includes a heterogeneous group of disorders, including kidney disease, and anemias, which can cause PH of varying severity.