Pulmonary hypertension is abnormally high blood pressure in the arteries of the lungs. It makes the right side of the heart need to work harder than normal.

Normally, the left side of the heart produces a high blood pressure in order to pump blood to the body. The right side of the heart pumps blood through the lungs under much lower pressure.

Pulmonary hypertension is usually caused by a narrowing of the small arteries of the lung. This narrowing makes it harder for the right side of the heart to circulate the blood to the lungs. Over time, the right side of the heart may become enlarged and een fail (cor pulmonale).

Pumonary hypertension may be caused by:

• A genetic defect
• Any condition that causes chronic low oxygen levels in the blood
• Autoimmune diseases, such as scleroderma
• Certain diet medications
• Congestive heart failure
• History of a blood clot in the lung
• HIV infection
• Lung or heart valve disease
• Obstructive sleep apnea

In many cases, the cause is unknown, in which case the condition is known as idiopathic pulmonary arteril hypertension (IPAH).

If it is caused by a known medicine or medical condition, it is called secondary pulmonary hypertension.

IPAH is rare. It affects more women than men.

• Chest pain, usually in the front of the chest
• Dizziness
• Fainting
• Fatigue
• Leg swelling
• Light-headedness during exercise
• Shortness of breath during activity
• Weakness

A physical examination may show:

• Abnormal heart sounds (especially a splitting of the second heart sound)
• Enlargement of the veins in the neck
• Feeling of a pulse over the breastbone
• Heart murmur
• Leg swelling
• Liver and spleen swelling
• Normal breathing sounds

In early stages of the disease, the exam may be normal or almost normal. The condition may take several months to diagnose. Asthma causes similar symptoms and must be ruled out.

Tests may include:

• Cardiac catheterization
• Chest x-ray
• CT scan of the chest
• Echocardiogram
• ECG
• Nuclear lung scan
• Pulmonary arteriogram
• Pulmonary function tests

There is no known cure. The goal of treatment is to control symptoms. When the pulmonary hypertension is brought on my another condition, then treatment is usually directed at that underlying disease.

Many new treatment options for idiopathic pulmonary arterial hypertension (IPAH) and other forms of pulmonary aterial hypertension are becoming available. Medicines used to treat pulmonary hypertension include:

• Ambrisentan (Letairis)
• Bosentan (Tracleer)
• Calcium channel blockers
• Diuretics
• Prostacyclin or similar medications
• Sildenafil

Your doctor will decide which medicine is best for you. You will be closely monitored during treatment to watch for side effects and how well you're responding to the medication.

Some patients are put on blood thinners to reduce the risk of blood clots in leg veins and lung arteries.

People with advanced cases of pulmonary arterial hypertension may need oxygen. If treatment with medications fails, suitable candidates may be helped by a lung or heart-lung transplant.

As the illness progresses, changes in the home environment and more help around the home will be needed.

The outlook has been poor, but new therapies may produce better results. Some people with this condition may develop progressive heart failure that may lead to death.

Call your health care provider if:

• You begin to develop shortness of breath when you are active
• Shortness of breath worsens
• You develop chest pain
• You develop other symptoms

Most patients with pulmonary arterial hypertension are treated at centers that specialize in the care of these patients.

Badesch DB, Abman SH, Simonneau G, et al. Medical Therapy for Pulmonary Arterial Hypertension Updated ACCP Evidence-Based Clinical Practice Guidelines. Chest. 2007: 131(6).

Barst RJ. Pulmonary hypertension. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 67.