Pulmonary hypertension refers to high blood pressure in the right side of the heart. However, there can be many different reasons for why PH may develop. The group of PH is determined by the underlying cause.
Group 1: Pulmonary arterial hypertension
Typically caused by congenital heart defects, genetic disorders, or other unknown causes.
Group 2: Pulmonary hypertension caused by left-sided heart disease
When the left side of the heart has a problem, it can cause the lower right ventricle (chamber) of the heart to also fail and cause PH.
Group 3: Pulmonary hypertension caused by lung disease
When the lungs themselves are underdeveloped (in the case of newborns) or have a disease such as chronic obstructive pulmonary disease (COPD), this can cause pressure to build up on the right ventricle of the heart and cause PH.
Group 4: Pulmonary hypertension caused by blood clots
Blood clots in the lungs (pulmonary emboli) is another identified cause of PH.
Group 5: Pulmonary hypertension associated with other conditions
Other unusual diseases or combination of diseases can precipitate PH such as a tumor, blood disorders, or other organ diseases.