AHA Recommendation
There is extremely wide variability in the severity of pulmonary hypertension
among various patients. Evaluating, accurately diagnosing and treating
the condition is also very complex. For these reasons, patients with
symptoms that suggest pulmonary hypertension require thorough evaluation
at a medical center with expertise and experience in pulmonary hypertension.
What is primary pulmonary hypertension (or unexplained pulmonary hypertension)?
Primary or unexplained pulmonary hypertension (PPH) is a rare lung
disorder in which the blood pressure in the pulmonary artery rises
far above normal levels for no apparent reason. The pulmonary artery
is a blood vessel carrying oxygen-poor blood from the right ventricle
(one of the heart's pumping chambers) to the lungs. In the lungs, the
blood picks up oxygen, then flows to the heart's left side, where the
left ventricle pumps it to the rest of the body through the aorta.
Hypertension is a medical term
for abnormally high blood pressure. Normal average (also called "mean")
pulmonary artery pressure is about 14 mm Hg at rest. In patients
with PPH, the average blood
pressure in the pulmonary artery is greater than 25 mm Hg at rest and
greater than 30 mm Hg during exercise. This abnormally high pressure
(pulmonary hypertension) is linked with changes in the small blood
vessels in the lungs. These changes increase resistance to blood flowing
through the vessels. This increased resistance puts a strain on the
right ventricle, which now must work harder than usual to move enough
blood through the lungs.
In the United States, an estimated 500 to 1,000 new cases of primary
pulmonary hypertension are diagnosed each year.
The greatest number is reported in women between ages 20 and 40. However,
men and women in all age ranges -- as well as very young children --
can develop PPH.
What causes primary pulmonary hypertension?
We don't know the cause; there may be one or more causes. The low
incidence makes learning more about the disease extremely difficult.
Studies of PPH also have been difficult because a good animal model
of the disease hasn't been available. We think that in most people
who develop primary pulmonary hypertension, the blood vessels are very
sensitive to certain factors that trigger this disease to develop.
For example, people with Raynaud's syndrome seem more likely than
others to develop PPH.
In addition, appetite suppressants, cocaine and HIV are some factors
believed to trigger the constriction, or narrowing, of the pulmonary
artery.
What are the symptoms of primary pulmonary hypertension?
The first symptom is often fatigue
or tiredness. Many patients think that they're simply "out
of shape."
Difficulty in breathing, dizziness and even fainting spells can occur.
Swelling in the ankles or legs, bluish discoloration of the lips and
skin, and chest pain more often occur later in the disease.
One of the great difficulties in treating PPH is that the diagnosis
is often delayed due to the slowly progressive and insidious onset
of the symptoms.
How is a patient with primary pulmonary hypertension evaluated?
Significant advances in PPH therapy over the past decade have markedly
affected the survival and quality of life for people with this disease.
The optimal medical and/or surgical treatment for patients with PPH
depends upon a thorough evaluation at a medical center with expertise
in pulmonary hypertension.
The evaluation includes a right heart cardiac catheterization. In
this procedure the doctor places a thin, flexible tube (a catheter)
through an artery or vein in the patient's arm, leg or neck, then threads
it into the right ventricle and pulmonary artery. This is the only
way to measure the pressure in the pulmonary artery and find out what
medical therapy is appropriate for a given patient.
What therapy is available for patients with primary pulmonary hypertension?
Doctors can choose from a variety of drugs that help lower blood pressure
in the lungs and improve heart performance in many patients. Physicians
now know that patients with PPH respond differently to the different
medications that dilate or relax blood vessels and that no one drug
is consistently effective in all patients. Because individual reactions
vary, different drugs have to be tried before chronic or long-term
treatment begins. During the course of the disease, the amount and
type of medicine also may have to be changed. To find out which medicine
works best for a particular patient, doctors evaluate the drugs during
cardiac catheterization.
At present, about one-quarter of patients can be treated with calcium
channel-blocking drugs given orally.
Intravenous prostacyclin is a vasodilator. It helps patients who don't
respond to treatment with calcium channel blockers given by mouth.
It's continuously delivered by a portable, battery-operated infusion
pump. Despite this complexity, prostacyclin improves pulmonary hypertension
and permits increased physical activity. This improves the quality
of life for patients of all ages. Prostacyclin is sometimes used as
a bridge to help patients waiting for a transplant. In other cases
it's used for long-term treatment.
Besides oral calcium channel blockers and chronic intravenous prostacyclin,
clinical trials are under way to evaluate new drugs to improve the
treatment of PPH. Some patients also do well by taking medicines that
make the right ventricle's work easier.
Anticoagulants, for example, can decrease the tendency of the blood
to clot, thus permitting the blood to flow more freely.
Diuretics reduce the amount of fluid in the body, further reducing
the amount of work the heart has to do.
Some patients also require supplemental oxygen delivered through nasal
prongs or a mask if breathing becomes difficult. Some need oxygen around
the clock.
Transplantation (heart-lung or lung) is reserved for patients who don't
respond to medical therapy. The decision whether a patient requires
heart-lung transplantation or lung transplantation is made after a
thorough evaluation at a lung transplantation center.
What are the long-term prospects for patients with primary pulmonary
hypertension?
Despite the complexity of some of the various medical therapies, accurate,
early diagnosis and initiation of treatment have saved the lives of
many patients with PPH. With optimal medical and/or surgical therapy,
patients can often return to a virtually normal lifestyle, including
running a household, returning to school and participating in many
physical activities.
Most doctors and patients agree that it's very important for both
patients and families to be as informed as possible. This lets everyone
understand the illness and apply the information to what is happening.
In addition to family and close friends, support groups can help PPH
patients. More information is available from these organizations:
Pulmonary Hypertension Association (PHA)
850 Sligo Avenue, Suite 800
Silver Spring, MD 20910
PPH Cure Foundation
1826 R Street, NW
Washington, DC 20009-1604
(202) 518-5477
Despite physicians' inability to cure primary pulmonary hypertension,
advances in its treatment over the past decade have markedly improved
survival and the quality of life for people with primary pulmonary
hypertension.
Much of the research and development of treatments have focused on
primary pulmonary hypertension. However, these same treatments are
now being evaluated in many patients with pulmonary hypertension due
to other causes, such as congenital heart disease or disorders such
as scleroderma or systemic lupus erythematosus.
GO TO - top of page
