What is idiopathic pulmonary arterial hypertension?

Idiopathic pulmonary arterial hypertension (IPAH) is a lung disorder characterized by high blood pressure in the pulmonary arteries. In this instance, “idiopathic” means that the cause of the pulmonary artery hypertension is unknown.

The primary job of your pulmonary arteries is to carry blood from the right side of your heart to your lungs. This disorder causes your blood to flow through the stiff and narrowed pulmonary artery with greater heart pumping force.

You’re diagnosed with this condition when the average blood pressure in your pulmonary arteries is higher than 25 mmHg (millimeters of mercury) while resting and higher than 30 mmHg while exercising.

IPAH and other forms of pulmonary hypertension are dangerous because high blood pressure in your pulmonary arteries strains your heart and causes serious heart and lung problems.

Symptoms of IPAH vary according to the stage of the disorder. It’s important to make a doctor’s appointment if you develop any unusual heart or lung symptoms.

You may have no symptoms during the early stage of this disorder. In fact, an annual physical may not detect this type of hypertension. As your condition progresses, you may experience the following:

  • tiredness
  • shortness of breath
  • fainting
  • dizziness
  • fast pulse
  • chest pain
  • heart palpitations
  • swelling in your lower extremities

In healthy blood vessels, blood flows smoothly and easily. If you have pulmonary hypertension, increased blood pressure occurs in thickened and narrowed arterial blood vessels in your lungs and reduces blood flow.

Possible known causes of pulmonary hypertension include:

Your risk for developing a form of pulmonary hypertension increases if you have:

  • a connective tissue disorder, such as scleroderma or systemic lupus erythematosus
  • cirrhosis of the liver
  • HIV and AIDS
  • a history of using drugs like cocaine or methamphetamines
  • a history of taking certain diet pills or appetite suppressants
  • a history of tobacco smoking
  • a history of occupational exposure to small particles such as sawdust

Pulmonary hypertension may also run in families, so your risk increases if you have a family history.

Note: While many forms of pulmonary hypertension have known triggers, idiopathic pulmonary arterial hypertension is different. IPAH occurs spontaneously and has no known cause.

Your doctor may run several tests, but they won’t be able to determine the underlying cause in IPAH. Although the cause is unknown, the condition is known to be more common in younger adults and females.

Regardless of whether you experience mild or intermittent symptoms, never ignore signs that indicate a problem with your heart or lungs. IPAH is a hard disorder to diagnose because some people don’t have symptoms. And when there are symptoms of IPAH, they’re similar to those of other heart and lung disorders.

To help diagnose the disorder, your doctor may look for swelling in the veins in your neck and then check your heart for abnormal sounds, such as a heart murmur.

Your doctor may also take various blood samples to measure your oxygen level and check for infections, elevated hemoglobin, thyroid problems, and vascular disorders.

Other possible tests to diagnose pulmonary hypertension include:

  • 12-lead electrocardiogram (EKG) to measure electrical activity in your heart
  • pulmonary function test to check lung function and see how well your lungs are working
  • right heart catheterization to see if there are problems with your heart’s blood supply
  • imaging studies (such as a chest X-ray, CT scan, MRI, nuclear scan, or echocardiogram) to take pictures of your lungs and heart and provide a visual of other chest structures, including your blood vessels
  • walking test, which involves walking for six minutes as a doctor monitors you for symptoms such as shortness of breath while measuring your activity tolerance and pulse oximetry

There is no readily available cure for idiopathic pulmonary hypertension. The goal of treatment is to control symptoms and slow the progression of the disorder. Treatment depends on the severity of your condition. Your doctor may recommend the following medications:

  • a calcium channel blocker to relax the muscles in the blood vessels and improve your heart’s ability to pump blood
  • a blood-thinning medication to prevent blood clots
  • diuretics to flush excess fluids from your body and reduce swelling
  • vasodilators to widen the lumen (interior) of the blood vessel in your lungs and improve blood flow
  • digoxin to limit the heart rate and improve the contractility of the heart (how hard the heart squeezes)
  • endothelin receptor antagonist, a targeted therapy to slow the progression of pulmonary hypertension

Since reduced blood flow can reduce your body’s oxygen supply and cause weakness, shortness of breath, and fatigue, your doctor may determine that you’re a candidate for supplemental oxygen therapy. If so, you’ll wear a tube that delivers oxygen from a tank into your nostrils.

If you have severe idiopathic pulmonary arterial hypertension, your doctor may suggest surgery. One option is a surgical procedure called an atrial septostomy, creating a cardiac shunt to increase blood flow from the right upper chamber to the left upper chamber of your heart. This procedure may help to improve oxygen levels in your body.

Another option is a lung, or heart and lung, transplantation with replacement of your organ(s) with that or those of a healthy donor. Transplant surgery may be an option if your condition worsens and doesn’t respond to other treatments.

Discuss the risks of surgery with your doctor, such as the risk of blood loss, infection, or organ rejection.

IPAH requires medical attention due to the risk of complications. If you don’t seek treatment, your condition will likely worsen much faster. High blood pressure in your pulmonary arteries can lead to irreversible damage to your heart and lungs.

The disorder can lead to right-sided heart enlargement and dysfunction. This complication causes your heart to work harder and can result in heart failure. It can also lead to abnormal heart rhythms, such as atrial fibrillation.

With treatment, improvement in your symptoms is possible. But if left untreated, the condition can worsen much faster and significantly reduce your life expectancy.

To improve your chance of slowing disease progression, follow your doctor’s recommended course of treatment and make healthy lifestyle changes:

  • Getting plenty of rest is important to cope with fatigue.
  • Sometimes, moderate exercises such as biking, swimming, and walking are effective for increasing or maintaining energy levels. Make sure you speak with your doctor before starting an exercise routine.
  • You should also avoid tobacco smoking and secondhand smoke, which can increase breathing difficulties.
  • Because pregnancy can be life-threatening with pulmonary hypertension, talk to your doctor about safe birth control alternatives. Be aware that certain birth control pills increase the likelihood of blood clots.

Other tips include:

  • avoiding traveling at high altitudes, which can make symptoms more severe
  • avoiding activities that lower blood pressure and increase the risk of fainting, such as long hot baths or sitting in a sauna
  • eating a diet low in saturated fat, cholesterol, and sodium to maintain a healthy blood pressure and weight

Family and friends can provide emotional and physical support. In addition, you can talk to your doctor about joining a support group to help you cope with and understand your condition.