What Is Pulmonary Hypertension?

Pulmonary hypertension, or PH, is increased pressure in the pulmonary arteries. These arteries carry blood from your heart to your lungs to pick up oxygen.

 

PH causes symptoms such as shortness of breath during routine activity, tiredness, chest pain, and a racing heartbeat. As the disease worsens, its symptoms may limit all physical activity.

 

Overview

 

The lower right chamber of your heart, the right ventricle, pumps blood to your pulmonary arteries. The blood then travels to your lungs, where it picks up oxygen. This oxygen-rich blood is pumped to the rest of your body. (Diseases and Conditions Index article on How the Heart Works.)

 

Three types of changes can affect the pulmonary arteries and cause PH:

 

These changes make it hard for the heart to push blood through the arteries and into the lungs. Thus, the pressure in the arteries rises. Also, as a result of the heart working harder, the right ventricle becomes strained and weak.

 

The heart may become so weak that it can't pump enough blood to the lungs. This causes heart failure. Heart failure is the most common cause of death in people who have PH.

 

PH is divided into five groups based on its causes. In all groups, the average pressure in the pulmonary artery is higher than 25 mmHg at rest or 30 mmHg during physical activity. The pressure in a normal pulmonary artery is about 15 mmHg at rest

 

Usually, other diseases or conditions, such as heart and lung diseases or blood clots, cause PH. Some people inherit the condition. In some cases, the cause isn't known.

 

Outlook

 

PH has no cure. However, research for new treatments is ongoing. The earlier PH is treated, the easier it is to control.Treatments include medicines, procedures, and other therapies. These treatments can relieve PH symptoms and slow the progress of the disease. Lifestyle changes also can help control symptoms.

 

"Strength does not come from physical capacity. It comes from an indomitable will."

 

Types of Pulmonary Hypertension

The World Health Organization divides pulmonary hypertension into five groups. These groups are organized based on the cause of the disease.

 

In all groups, the average pressure in the pulmonary artery is higher than 25 mmHg at rest or 30 mmHg during physical activity. The pressure in a normal pulmonary artery is about 15 mmHg at rest.

 

Group 1 PAH includes:

 

Group 2 includes PH with left heart disease. Conditions that affect the left side of the heart, such as mitral valve disease or long-standing high blood pressure, can cause left heart disease and PH.

 

Group 3 includes PH linked to lung conditions such as COPD (chronic obstructive pulmonary disease) and interstitial lung disease. Interstitial lung disease refers to a group of lung diseases that cause scarring of the lung tissue. Group 3 also includes PH linked to sleep disorders that cause breathing problems, such as sleep apnea.

 

Group 4 includes PH due to blood clots in the lungs or blood clotting disorders. This group also includes PH due to sickle cell anemia.

 

Group 5 includes PH due to various other diseases or conditions. Examples include sarcoidosis, Langerhans cell histiocytosis, and lymphangioleiomyomatosis (LAM). This type of PH also may be due to an object, such as a tumor, pressing on the pulmonary blood vessels.

 

Sometimes other terms are used to describe the different types of PH. Group 1 PAH that has no known cause may be called primary or idiopathic PAH. When PH occurs with or is caused by another disease or condition, it may be called secondary PH.

 

What Causes Pulmonary Hypertension?

Pulmonary hypertension is the result of a process that begins with changes in the cells that line your lungs' arteries. This process includes three types of changes that affect the pulmonary arteries:

 

These changes make it hard for the heart to push blood through the arteries and into the lungs.

 

Thus, the pressure in the arteries rises, resulting in PH.

 

A number of different factors can contribute to the process that leads to the different types of PH.

 

Group 1 pulmonary arterial hypertension may have no known cause, or it may be inherited (passed from parents to children through the genes). Certain diseases and conditions, such as congenital heart diseae, HIV, and thyroid disease, also can cause this type of PH. Also, the use of certain diet medicines and street drugs can lead to this type of PH.

 

Many different diseases and conditions can lead to the development of groups 2 through 5 PH (often called secondary PH), including:

 

 

Who Is At Risk for Pulmonary Hypertension?

The exact number of people who have pulmonary hypertension isn't known. Group 1 pulmonary arterial hypertension without a known cause is rare. PH that occurs with another disease or condition is more common.

 

Anyone can develop PH. However, PAH that has no known cause affects about two to three times as many women as men. PH usually develops between the ages of 20 and 60, but it can occur at any age.

 

People who are at increased risk for PH include: