Primary pulmonary hypertension (PPH) is now known as pulmonary arterial hypertension (PAH). The name was changed in 1998 to pulmonary arterial hypertension (PAH) because it was determined to be more descriptive of the condition (Loyd, 2011).
PAH is a disorder characterized by an abnormal increase in pulmonary artery pressure (PAP), normal pulmonary capillary wedge pressure (PCWP), and increased pulmonary vascular resistance (PVR). A gradual increase of pressure in the pulmonary veins can lead to eventual right-heart failure and death. Increases in pulmonary arterial pressure are the most important indicators of PAH.
Imaging tests are used to look inside the body for a diagnosis. Enlarged arteries or damage to the heart is a sure sign of PAH. Medications are used to slow heart damage and deal with symptoms.
Even with treatment, about one-third of people with PAH will die within three years of diagnosis (Loyd, 2011). Thanks to new treatments this number is an improvement from the 50 percent who used to die within three years. The hope is that a cure will be found to stop the damage of PAH.
PAH is still not well understood. Research has found certain diseases that may make a person more likely to develop PAH:
- human immunodeficiency virus (HIV) infection–the exact link is unknown, but the rate for developing PAH is 0.5 percent—six times higher than in the general population (Natarajan, 2011)
- mutation in the 2(BNP2) gene–present in 70 percent of cases of FPAH (Natarajan, 2011)
- portal hypertension–PAH is noted in about six percent of people with portal hypertension (increased pressure in the veins that carry blood from the gastrointestinal tract and organs to the liver).(Natarajan, 2011)
- unrepaired, inherited chronic heart disease
The cause of PAH can be either idiopathic (IPAH) or familial (FPAH). Idiopathic diseases arise spontaneously, and their causes are unknown. FPAH diseases are genetically passed down through families.
Most cases of FPAH arise from a mutation in the BMPR2 gene. Severe cases are generally linked to the presence of the mutation. Although the mutation may be present at birth, the disease may take years or months to appear.
Environmental factors and medications are believed to be possible causes of IPAH.
Possible causes of IPAH:
- appetite suppressants (aminorex, fenfluramine, dexfenfluramine, etc.)
- hormone therapy (possible theory to explain why more females than males have the disease)
The characteristic symptom of PAH is an increase in pulmonary vascular resistance (PVR). This causes an increase in pressure on the right ventricle of the heart. That problem leads to trouble in filling the left part of the heart. The result is eventual heart failure.
Common symptoms of PAH are:
- dyspnea (difficult or labored breathing) on exertion
- fatigue caused by the heart having to pump harder and harder
- near syncope (near fainting)
- syncope (fainting)
Diagnosis is not easy because damage inside the heart cannot be seen during a routine examination. Doctors try to rule out all other causes of pulmonary hypertension before a diagnosis is made. Your doctor may order some or all of the following tests:
- electrocardiogram (EEG)–looks for proof of right ventricle damage or strain
- chest X-ray (CXR)–looks for enlarged arteries from the overworking heart
- computed tomography (CT) scan–clearer than CXR; used to see enlarged pulmonary arteries and the right ventricle
- transthoracic echocardiography–uses sound waves to look at the size and motion of the heart, function of the heart valves, etc. (essential for diagnosis)
- six-minute test–used to assess exercise endurance by having the patient be physically active for six minutes
- lung biopsy–done only if PAH is not assumed to be your primary disease
Treatments for PAH are meant to reduce symptoms and extend survival time. Doctors often begin treatments late in the disease because of poor detection.
The FDA has approved several medications for dealing with PAH. They are able to ease symptoms and improve physical function. None of the medications can completely relieve the symptoms of PAH and some they are extremely expensive, costing upward of $175,000 a year (Loyd, 2011).
Medication options include:
- prostacyclins–first new treatment for pulmonary hypertension
- endothelial receptor antagonists–tightens blood vessels
- phosphodiesterase inhibitors–relaxes muscles of the arterial walls to widen blood vessels
Other treatment options include:
- lung transplantation–only done in specific cases
- restriction of physical activity
Although modern treatment has come a long way, one-third of all patients with PAH will die within three years of diagnosis.
Death is an expectation and a common occurrence with PAH because no cure or effective treatment exists. Medications that are available to treat symptoms can extend life for a while, but they cannot stop the eventual terminal heart failure.