Pulmonary arterial hypertension (PAH) is a disorder that causes the blood vessels inside the lungs to become narrowed, which causes hypertension (high blood pressure) in the lungs as well as the right side of the heart. Over time, this can lead to right-sided heart failure, irregular heartbeat, blood clots, and bleeding in the lungs. PAH can also cause complications during pregnancy.
Though PAH can affect anyone at any age, it is more common among females ages 30 to 60 and people who are 65 or older.
PAH is not often detected on routine health screenings. Even when symptoms are present, symptoms overlap with more common heart and lung conditions, such as asthma, COPD, and heart failure. Misdiagnoses and delays in diagnosis are common. Diagnosing PAH involves ruling out these other health conditions and other potential causes of pulmonary hypertension.
A diagnosis can be confirmed with a test called right heart catheterization. This test uses a thin tool inserted into a vein to directly measure blood pressure and oxygen in the lungs and heart.
Some cases of PAH are associated with underlying medical conditions. Some cases are associated with genetic mutations inherited from a person’s biological parents. Many cases are idiopathic, where there is no identifiable cause.
Research into the underlying genetics of PAH is ongoing.
Recognizing the risk factors for PAH
People who have a known family history of PAH should be aware of the signs and symptoms of the disease, and in some cases, they may be advised by a healthcare provider to consult with a genetic counselor.
A genetic counselor is a healthcare provider with specialized training in medical genetics. This provider works with individuals and families to help them understand their risk of a genetic disease, weigh the risks and benefits of genetic testing, and interpret test results for those who do proceed with genetic testing.
As mentioned above, some cases of PAH are associated with other health conditions or risk factors, which may contribute to the development of PAH. These conditions include:
- Autoimmune diseases that affect connective tissues, including mixed connective tissue disease, scleroderma, and systemic lupus erythematosus (SLE)
- HIV infection
- Congenital heart disease
- Glycogen storage diseases
- Liver disease and portal hypertension (elevated blood pressure associated with liver disease)
- The use of certain drugs, like methamphetamines and cocaine
- Schistosomiasis (a parasitic infection, uncommon in the United States)
What are the symptoms of PAH?
PAH is a progressive condition, where symptoms get worse over time. In the early stages, a person may not notice symptoms or may only notice mild symptoms. As the disease progresses, more severe signs and symptoms of PAH will appear.
Common signs and symptoms include:
- Shortness of breath, especially during activity
- Fatigue
- Dizziness, lightheadedness, and/or fainting spells
- Chest pain or feelings of pressure on the chest
- Swelling in the feet, ankles, or abdomen caused by fluid buildup
- Bluish fingers or lips (caused by low oxygen)
- Abnormal heart rhythms, including pounding or racing heartbeat
- Abnormal heart sounds, which are the sounds created by blood moving through the heart chambers and heart valves opening and closing
Again, these signs and symptoms can overlap with many other conditions, including other types of pulmonary hypertension. Your best source of information will always be a healthcare team. If you have a family history of PAH, your own risk is something that you should discuss with your healthcare provider.
If you have any of the associated conditions or risk factors mentioned above, talk to your healthcare provider about how this may impact your health, what signs and symptoms you need to watch for, and how to keep yourself as healthy as possible.
Any symptoms like those mentioned above—symptoms that affect breathing or heartrate, or cause pain or discomfort in the chest—should always be evaluated by a healthcare provider.
Sources: MedlinePlus Genetics. Pulmonary arterial... + 15
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