Pulmonary Hypertension : Pathophysiology and Management

Pulmonary hypertension is a type of high blood pressure that affects the arteries in the lungs and the right side of the heart.

In one form of pulmonary hypertension, called pulmonary arterial hypertension (PAH), blood vessels in the lungs are narrowed, blocked or destroyed. The damage slows blood flow through the lungs. Blood pressure in the lung arteries goes up. The heart must work harder to pump blood through the lungs. The extra effort eventually causes the heart muscle to become weak and fail.

In some people, pulmonary hypertension slowly gets worse and can be life-threatening. There's no cure for pulmonary hypertension. But treatments are available to help you feel better, live longer and improve your quality of life.

Symptoms

The symptoms of pulmonary hypertension develop slowly. You may not notice them for months or even years. Symptoms get worse as the disease progresses.

Pulmonary hypertension symptoms include:

• Shortness of breath, at first while exercising and eventually while at rest.

• Blue or gray skin color due to low oxygen levels. Depending on your skin color, these changes may be harder or easier to see.

• Chest pressure or pain.

• Dizziness or fainting spells.

• Fast pulse or pounding heartbeat.

• Fatigue.

• Swelling in the ankles, legs and belly area.

Shortness of breath is the most common symptom of pulmonary hypertension. But it may be caused by other health conditions such as asthma. See a health care professional for an accurate diagnosis.

The typical heart has two upper chambers and two lower chambers. Each time blood moves through the heart, the lower right chamber pumps blood to the lungs. The blood passes through a large blood vessel called the pulmonary artery.

Blood usually flows easily through blood vessels in the lungs to the left side of the heart. These blood vessels are the pulmonary arteries, capillaries and veins.

But changes in the cells that line the lung arteries can cause the artery walls to become narrow, stiff, swollen and thick. These changes may slow down or stop blood flow through the lungs, causing pulmonary hypertension.

Pulmonary hypertension is classified into five groups, depending on the cause.

Group 1: Pulmonary arterial hypertension (PAH)

Causes include:

• Unknown cause, called idiopathic pulmonary arterial hypertension.

• Changes in a gene passed down through families, called heritable pulmonary arterial hypertension.

• Use of some medicines or illegal drugs, including methamphetamine.

• Heart problems present at birth, called a congenital heart defect.

• Other health conditions, including scleroderma, lupus and chronic liver disease such as cirrhosis.

Group 2: Pulmonary hypertension caused by left-sided heart disease

This is the most common form of pulmonary hypertension. Causes include:

• Left heart failure.

• Left-sided heart valve disease such as mitral valve or aortic valve disease.

Group 3: Pulmonary hypertension caused by lung disease

Causes include:

• Scarring of the lungs, called pulmonary fibrosis.

• Chronic obstructive pulmonary disease.

• Sleep apnea.

• Long-term exposure to high altitudes in people who may be at higher risk of pulmonary hypertension.

Group 4: Pulmonary hypertension caused by chronic blood clots or blockages in the pulmonary artery

Causes include:

• Chronic blood clots in the lungs, called pulmonary emboli.

• Tumors that block the pulmonary artery.

Group 5: Pulmonary hypertension triggered by other health conditions

Causes include:

• Blood disorders, including polycythemia vera and essential thrombocythemia.

• Inflammatory disorders such as sarcoidosis.

• Metabolic disorders, including glycogen storage disease.

• Kidney disease.