How Is Pulmonary Hypertension Diagnosed?

Your doctor will diagnose pulmonary hypertension (PH) based on your medical and family histories, a physical exam, and the results from tests and procedures.

PH can develop slowly. In fact, you may have it for years and not know it. This is because the disease has no early symptoms.

When symptoms do develop, they're often like those of other heart and lung conditions, such as asthma. This makes PH hard to diagnose.

Medical and Family Histories

To learn about your medical history, your doctor may ask about your signs and symptoms and how and when they began. He or she also may ask whether you have other medical conditions that can cause PH.

Your doctor also may ask whether you have any family members who have or have had PH. People who have a family history of PH are at increased risk for the condition.

Physical Exam

During the physical exam, your doctor will listen to your heart and lungs with a stethoscope. He or she also will check your ankles and legs for swelling and your lips and skin for a bluish tint. These are signs of PH.

Diagnostic Tests and Procedures

You may need tests and procedures to confirm a diagnosis of PH and to look for the underlying cause of the disease. Your doctor also will use test results to find out the severity of your PH.

Tests and Procedures To Confirm a Diagnosis

Echocardiography. This test uses sound waves to create a moving picture of your heart. Echocardiography (EK-o-kar-de-OG-ra-fee) can estimate the pressure in your pulmonary arteries. The test also can show the size and thickness of your right ventricle and how well it's working.

Chest x ray. A chest x ray takes pictures of your heart and lungs. This test can show whether your pulmonary arteries and right ventricle are enlarged. The pulmonary arteries and right ventricle may get larger if the right ventricle has to work hard to pump blood through the pulmonary arteries.

Also, a chest x ray may show signs of an underlying lung disease that may be causing or contributing to PH.

EKG (electrocardiogram). An EKG is a simple test that shows how fast your heart is beating. It also shows whether your heart's rhythm is steady or irregular. An EKG may show whether your right ventricle is enlarged or strained.

Right heart catheterization. This procedure measures the pressure in your pulmonary arteries. It also shows how well your heart is pumping blood to the rest of your body. Right heart catheterization (KATH-e-ter-i-ZA-shun) can find any leaks between the left and right side of the heart.

During this procedure, a thin, flexible tube called a catheter is put into a blood vessel in your groin (upper thigh) or neck. The tube is then threaded into the right side of your heart and into the pulmonary arteries. Through the tube, your doctor can do diagnostic tests and test treatments on your heart.

Tests To Look for the Underlying Cause of Pulmonary Hypertension

Lung function tests. Lung function tests measure the size of your lungs, how much air you can breathe in and out, how fast you can breathe air out, and how well your lungs deliver oxygen to your blood. These tests can help find an underlying lung disease that may be causing PH.

Overnight oximetry. This test measures the level of oxygen in your blood overnight. A low oxygen level during sleep is common in PH, and it can cause the condition to worsen.

For this test, a small light is attached to your fingertip, earlobe, or toe. A machine that's attached to the light measures the amount of oxygen in your blood throughout the night. In the morning, the light is removed and your oxygen levels are recorded. Overnight oximetry can be done at home or in a sleep lab.

Lung ventilation/perfusion (VQ) scan. This test measures air and blood flow in your lungs. A lung VQ scan can show whether there are blood clots in your lung's blood vessels.

Blood tests. Blood tests are used to rule out other diseases, such as HIV, liver disease, and autoimmune diseases like rheumatoid arthritis.

Exercise testing. Exercise testing consists of either a 6-minute walk test or a cardiopulmonary exercise test. These tests can help find out whether another disease or condition is causing your symptoms.

A 6-minute walk test measures the distance you can quickly walk in 6 minutes. A cardiopulmonary exercise test measures how well your lungs and heart work while you exercise on a treadmill or bicycle.

Finding Out the Severity of Pulmonary Hypertension

Exercise testing is used to find out how severe PH is. During this test, your doctor will rate your activity level. Your level is linked to how severe your PH is. The rating system ranges from class 1 to class 4.

• Class 1 has no limits. You can do regular physical activities, such as walking or climbing stairs. These activities don't cause PH symptoms, such as tiredness, shortness of breath, or chest pain.
• Class 2 has slight or mild limits. You're comfortable while resting, but regular physical activity causes PH symptoms.
• Class 3 has marked or noticeable limits. You're comfortable while resting. However, walking even one or two blocks or climbing one flight of stairs can cause PH symptoms.
• Class 4 has severe limits. You're not able to do any physical activity without discomfort. You also may have PH symptoms while at rest.

Over time, you may need more exercise tests to find out how well your treatments are working. Each time testing is done, your doctor will compare your activity level to the previous one.