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Pulmonary hypertension (PH) is a rare but very complex and serious lung disease that is progressive and potentially fatal. PH is defined by high blood pressure in the lungs resulting from inflammation or scarring in the pulmonary arteries. If left untreated, PH can lead to enlargement and weakness of the right-side of the heart, a serious type of heart failure.
  • PH is characterized by the presence of high blood pressure in the lungs.
  • PH can lead to right-sided heart failure.
  • PH can strike people of all backgrounds, ages, and sex.



Pulmonary arterial hypertension (PAH):

WHO Group 1 

  • Idiopathic
  • Associated conditions (e.g. scleroderma)
  • Heritable

PAH is a disease in which blood is not able to circulate normally in the lungs due to narrowing of the arteries. This results in increased blood pressure in the lungs, causing the heart to work harder to pump blood into the lungs.

The heart can become enlarged, leading to right-sided heart failure and even death.

PH associated with left-sided heart disease:
WHO Group 2 

  • Heart failure (also known as congestive or left-sided heart failure)
  • Mitral or aortic valve disease

PH associated with lung disease:
WHO Group 3 

  • COPD
  • Pulmonary fibrosis
  • Sleep apnea

Chronic thromboembolic pulmonary hypertension (CTEPH):
WHO Group 4 

CTEPH is caused by blood clots that do not entirely dissolve following pulmonary embolism, leading to the formation of scars within the pulmonary arteries that impede blood ow into the lungs.

After pulmonary embolism, up to 4% of patients may develop CTEPH within 2 years.

PH caused by various other diseases:
WHO Group 5 

  • Certain hematologic conditions (sickle cell disease, myeloproliferative neoplasms)
  • Sarcoidosis
  • Many others
What is PH (Dr. Granton)