You’ve probably heard of high blood pressure (hypertension), a common condition that affects the way your blood flows through the arteries in your body from the left side of your heart. A less common type of high blood pressure, called pulmonary hypertension, affects only the arteries in the lungs and the right side of your heart.
Pulmonary hypertension begins when tiny arteries in your lungs, called pulmonary arteries and capillaries, become narrowed, blocked or destroyed. This makes it harder for blood to flow through your lungs, which raises pressure within the pulmonary arteries. As the pressure builds, your heart’s lower right chamber (right ventricle) must work harder to pump blood through your lungs, eventually causing your heart muscle to weaken and sometimes fail completely.
Pulmonary hypertension is a serious illness that becomes progressively worse and is sometimes fatal. Although it isn’t curable, treatments are available that can help lessen symptoms and improve your quality of life if you have pulmonary hypertension.
Signs and symptoms
The signs and symptoms of pulmonary hypertension are subtle in the early stages of the disease and may not be noticeable for months or even years. As the disease progresses, signs and symptoms become worse. They include:
- Shortness of breath (dyspnea), either while exercising or at rest
- Dizziness or fainting spells (syncope)
- Chest pressure or pain
- Swelling (edema) in your ankles, legs and eventually in your abdomen (ascites)
- Bluish color to your lips and skin (cyanosis)
- Racing pulse or heart palpitations
Your heart has two upper and two lower chambers. Each time blood passes through your heart, the lower right chamber (right ventricle) pumps blood to your lungs through a large blood vessel (pulmonary artery). In your lungs, the blood releases carbon dioxide and picks up oxygen. The oxygen-rich blood then flows through the pulmonary veins to the left side of your heart. From there, it’s pumped by the left ventricle to the rest of your body through another large blood vessel, the aorta.
Ordinarily, the blood flows easily through the vessels in your lungs, so your blood pressure is usually much lower in your lungs. With pulmonary hypertension, the rise in blood pressure is the end result of a process that begins with changes in the cells that line your lungs’ arteries. These changes cause the formation of extra tissue that eventually narrows or completely blocks the blood vessels. Scarring (fibrosis) usually also occurs, making the arteries stiff and narrow. This makes it harder for blood to flow, raising the pressure in the pulmonary arteries.
Idiopathic pulmonary hypertension
When an underlying cause for high blood pressure in the lungs can’t be found, the condition is called idiopathic pulmonary hypertension (IPH) or primary pulmonary hypertension (PPH).
Some people with IPH have an inherited predisposition for the disease, which may be confirmed by a genetic test. But in most people with idiopathic pulmonary hypertension, there is no recognized cause of their pulmonary hypertension.
Secondary pulmonary hypertension
Pulmonary hypertension resulting directly from another medical problem is called secondary pulmonary hypertension. This type of pulmonary hypertension is more common than idiopathic pulmonary hypertension. Medical conditions that may lead to secondary pulmonary hypertension include:
- Blood clots in the lungs (pulmonary emboli)
- Chronic obstructive pulmonary diseases, such as emphysema
- Connective tissue disorders, such as scleroderma
- Sleep apnea
- Congenital heart disease
- Sickle cell anemia
- Chronic liver disease (cirrhosis)
- Lung diseases such as pulmonary fibrosis, a condition that causes scarring in the tissue between the lungs’ air sacs (interstitium)
- Left-sided heart failure
If you live above an altitude of 8,000 feet you can develop pulmonary hypertension as a result of low blood oxygen (hypoxemia) or pulmonary edema (a condition in which the air sacs in the lungs fill with fluid instead of air), which constricts the small pulmonary arteries. People who climb to high elevations without first becoming acclimated are especially at risk of developing a temporary form of pulmonary hypertension known as transient reversible pulmonary hypertension.
Although the exact cause of secondary pulmonary hypertension isn’t known, it’s possible that some who develop the disorder are especially sensitive to substances that cause the blood vessels to constrict. Cocaine and the diet drug fenfluramine, which was withdrawn from the market in 1997, are two of the substances that may contribute to IPH in some people.
Although medical treatment can’t cure pulmonary hypertension, it can lessen symptoms. You should also:
- Get plenty of rest. Getting ample rest can reduce the fatigue that may accompany pulmonary hypertension.
- Stay as active as possible. Even the mildest forms of activity may be too exhausting for some people with pulmonary hypertension. For others, moderate exercise such as walking may be of great benefit, and using oxygen during exercise may be especially helpful. But first, talk to your doctor aboutspecific exercise restrictions. In most cases, it’s recommended that you not lift more than 50 pounds (22.7 kilograms). Your doctor can help you plan an appropriate exercise program.
- Don’t smoke. If you smoke, the single most important thing you can do for your heart and lung health is to stop. If you can’t stop smoking by yourself, ask your doctor to prescribe a treatment plan to help you quit. Also, avoid secondhand smoke if possible.
- Avoid becoming pregnant or using birth control pills. If you’re a woman of childbearing age, avoid becoming pregnant. Pregnancy can be life-threatening for both you and your baby. Also avoid using birth control pills, which can increase your risk of blood clots. Talk to your doctor about alternative forms of birth control.
- Avoid traveling to or living at high altitudes. High altitudes can aggravate the symptoms of pulmonary hypertension. If you live at a high altitude, your doctor may advise you to move to a lower elevation.
- Avoid situations that can excessively lower blood pressure. These include sitting in a hot tub or sauna or taking long hot baths or showers. These activities lower your blood pressure and cause fainting or even death. You should also avoid activities that cause prolonged straining, such as lifting heavy objects or weights.
- Find ways to reduce stress. These can range from yoga, meditation and biofeedback to warm baths, music or a good book. Try to allow at least 30 minutes a day for an activity you find relaxing. Many people with pulmonary hypertension find that simply reducing stress can greatly improve the quality of their lives.
- Follow a nutritious diet and maintain a healthy weight. Ask your doctor for guidelines regarding salt intake. For most people with pulmonary hypertension sodium (salt) restriction will be recommended to minimize swelling of your body’s tissues (edema). Most experts agree that you should eat no more than 1,500 to 2,400 milligrams of salt a day. Keep in mind that processed foods often are very high in salt content, so it will be important to check labels carefully.
Although anyone can develop either type of pulmonary hypertension, older adults are more likely to have secondary pulmonary hypertension and young people are more likely to have idiopathic pulmonary hypertension (also called primary pulmonary hypertension). Primary pulmonary hypertension is also more common in women than it is in men.
Another risk factor for pulmonary hypertension is a family history of the disease. Some genes could be linked to idiopathic pulmonary hypertension. These genes might cause an overgrowth of cells in the small arteries of your lungs, making them narrower.
If one of your family members develops idiopathic pulmonary hypertension and tests positive for a gene mutation that can cause pulmonary hypertension, your doctor or genetic counselor may recommend that you or your family members be tested for the mutation.
Pulmonary hypertension Screening and diagnosis
Pulmonary hypertension is hard to diagnose early because it’s not often detected in a routine physical exam. Even when the disease is more advanced, its signs and symptoms often mimic those of other heart and lung conditions. An echocardiogram is usually used to diagnose pulmonary hypertension. However, your doctor may do one or more tests to rule out other possible reasons for your condition. Tests to diagnose pulmonary hypertension include:
- Echocardiogram. Your doctor may first suspect you have pulmonary hypertension based on the results of this test. This noninvasive test uses harmless sound waves that allow your doctor to see your heart without making an incision. During the procedure, a small, plastic instrument called a transducer is placed on your chest. It collects reflected sound waves (echoes) from your heart and transmits them to a machine that uses the sound wave patterns to compose images of your beating heart on a monitor. These images show how well your heart is functioning, and recorded pictures allow your doctor to measure the size and thickness of your heart muscle. Sometimes your doctor will recommend an exercise echocardiogram to help determine how well your heart works under stress. In that case, you’ll have an echocardiogram before exercising on a stationary bike or treadmill and another test immediately afterward.
- Transesophageal echocardiogram. If it’s difficult to get a clear picture of your heart and lungs with a standard echocardiogram, your doctor may recommend a transesophageal echocardiogram. In this procedure, a flexible tube containing a transducer is guided down your throat and into your esophagus. From this vantage point, the transducer can obtain detailed images of your heart.
- Pulmonary function test. This noninvasive test measures how much air your lungs can hold, and the airflow in and out of your lungs. During the test, you’ll blow into a simple instrument called a spirometer.
- Perfusion lung scan. This test uses small amounts of radioactive substances (radioisotopes) to study blood flow (perfusion) in your lungs. The radioisotopes are injected into a vein in your arm. Immediately afterward, a special camera (gamma camera) takes pictures of blood flow in your lungs’ blood vessels. A lung scan is then used to determine whether blood clots are causing symptoms of pulmonary hypertension. It’s usually performed with another test known as a ventilation scan. In this test, you inhale a small amount of radioactive substance while a gamma camera records the movement of air into your lungs. The two-test combination is known as a ventilation-perfusion (V/Q) scan, and in its entirety usually takes less than an hour with side effects or complications rarely occurring.
- Right heart catheterization. Performed on an outpatient basis using local anesthesia, this test is often the most reliable way of diagnosing pulmonary hypertension. During the procedure, a cardiologist places a thin, flexible tube (catheter) into a vein in your neck or groin. The catheter is then threaded into your right ventricle and pulmonary artery. Right heart catheterization allows your doctor to directly measure the pressure in the main pulmonary arteries and right ventricle. It’s also used to evaluate the effect different drugs may have on your heart in order to find the most effective treatment.
- Computerized tomography (CT). A CT scan allows your doctor to see your organs in two-dimensional “slices.” In this test, you’ll lie in a machine that takes images of your lungs so that your doctors can see a cross-section of them. You might also be given a medication that makes the images of your lungs show up more clearly.
- Magnetic resonance imaging (MRI). This test uses no X-rays. Instead, a computer creates tissue “slices” from data generated by a powerful magnetic field and radio waves. It can’t, however, measure artery pressure — a procedure that’s necessary if you’re taking medications to control IPH. But it can get good images of the pulmonary vessels.
- Genetic tests. If a family member has had pulmonary hypertension, your doctor may screen you for genetic mutations that are linked with pulmonary hypertension to confirm a diagnosis. If you test positive, your doctor may recommend that other family members be screened for the same genetic mutation.
- Open-lung biopsy. In rare situations your doctor may recommend an open-lung biopsy. An open-lung biopsy is a type of surgery in which a small sample of tissue is removed from your lungs to check for pulmonary hypertension.
While shortness of breath is one of the first symptoms of pulmonary hypertension, this symptom is also common with many other diseases, such as asthma. But, if you’re constantly short of breath, rather than only occasionally as is usually the case with asthma, see your doctor.
Pulmonary hypertension classifications
Once you’ve received a diagnosis of pulmonary hypertension, your doctor may classify the disease using guidelines developed by the New York Heart Association.
- Class I. Although you’ve been diagnosed with pulmonary hypertension, you have no symptoms.
- Class II. You don’t have symptoms at rest, but you experience fatigue, shortness of breath or chest pain with normal activity.
- Class III. You’re comfortable at rest but have symptoms with slight exertion.
- Class IV. You have symptoms even at rest.
Pulmonary hypertension Complications
Pulmonary hypertension can lead to a number of complications, including:
- Right-sided heart failure (cor pulmonale). In this condition, your heart’s right ventricle becomes enlarged and has to pump harder than usual to move blood through narrowed or blocked pulmonary arteries. Initially, the heart tries to compensate by thickening its walls and expanding the chamber of the right ventricle to increase the amount of blood it can hold. But this measure works only temporarily, and eventually the right ventricle fails from the extra strain.
- Blood clots. Clots are the end result of a complex process that helps stop bleeding after you’ve been injured. But sometimes clots form where they’re not needed. A number of small clots or just a few large ones can lead to pulmonary hypertension, which is reversible with time and treatment. Having pulmonary hypertension makes it more likely you’ll develop clots in the small arteries in your lungs, which is dangerous if you have narrowed or blocked blood vessels.
- Arrhythmia. Irregular heartbeats from the upper or lower chambers of the heart are complications of pulmonary hypertension. These can lead to palpitations, dizziness or fainting and can be fatal.
- Bleeding. Pulmonary hypertension can lead to bleeding into the lungs and coughing up blood (hemoptysis). This is another potentially fatal complication.
Pulmonary hypertension Treatment
The treatments are often complex and require extensive follow-up care. Your doctor may also need to change your treatment because it’s no longer effective. The best approach for you will depend on a number of factors, including your age, the type and class of pulmonary hypertension, and your overall health. When pulmonary hypertension is the result of another condition, your doctor will treat the underlying cause whenever possible.
Treatments for pulmonary hypertension include the following:
- Blood vessel dilators. These medications, also known as vasodilators, open narrowed blood vessels. One of the most commonly prescribed vasodilators for pulmonary hypertension is epoprostenol (Flolan). The drawback to epoprostenol is that its effects last only a few minutes. This drug is continuously injected through an intravenous (IV) catheter via a small pump that you wear in a pack on your belt or shoulder. This means that you’ll learn to prepare your own medication mixture, operate the pump and care for the IV catheter. You’ll need comprehensive follow-up care. Potential side effects of epoprostenol include jaw pain, nausea, diarrhea, leg cramps, as well as pain and infection at the IV site.A newer form of the drug, iloprost (Ventavis), avoids many of these problems. Iloprost can be inhaled every three hours through a nebulizer, a machine that vaporizes your medication, making it far more convenient and less painful to use. And because it’s inhaled, it goes directly to the lungs. Side effects associated with iloprost include chest pain — often accompanied by headache and nausea — and breathlessness.
- Endothelin receptor antagonists. These medications reverse the effect of endothelin, a substance in the walls of blood vessels that causes them to narrow. One of these medications, Bosentan (Tracleer), may improve your stamina and symptoms. The drug isn’t for pregnant women. If you take this, you’ll need monthly liver monitoring because the drug can damage your liver.
- Sildenafil. Revatio, a medication that contains sildenafil, the same active ingredient as the impotence drug Viagra, is sometimes used to treat pulmonary hypertension. It works by opening the blood vessels in the lungs. Side effects include dizziness and vision problems.
- High-dose calcium channel blockers. These drugs help relax the muscles in the walls of your blood vessels. They include medications such as amlodipine (Norvasc), diltiazem (Cardizem, Tiazac) and nifedipine (Adalat, Procardia). Although calcium channel blockers can be effective, only a small number of people with pulmonary hypertension respond to them.
- Ambrisentan. Ambrisentan (Letairis) is another medication that stops the narrowing of your blood vessels. Because of the risk of liver damage, and to minimize the risks to unborn children, you can only be prescribed ambrisentan through the Letairis Education and Access Program (LEAP). Before taking the drug, tell your doctor about any liver conditions you have.
- Anticoagulants. Your doctor is likely to prescribe the anticoagulant warfarin (Coumadin) to help prevent the formation of blood clots within the small pulmonary arteries. Because anticoagulants prevent normal blood coagulation, they increase your risk of bleeding complications. Take warfarin exactly as prescribed, because warfarin can cause severe side effects if taken incorrectly. If you’re taking warfarin, your doctor will ask you to have periodic blood tests to check how well the drug is working. Many other drugs, herbal supplements and foods can interact with warfarin, so be sure your doctor knows all of the medications you’re taking.
- Diuretics. Commonly known as water pills, these medications help eliminate excess fluid from your body. This reduces the amount of work your heart has to do. They also may be used to limit fluid buildup in your lungs.
- Oxygen. Your doctor may suggest that you sometimes breathe pure oxygen, a treatment known as oxygen therapy, to help treat pulmonary hypertension, especially if you live at a high altitude or have sleep apnea. Some people with pulmonary hypertension eventually require constant oxygen therapy.
- Transplantation. In some cases, a lung or heart-lung transplant may be an option, especially for younger people who have idiopathic pulmonary hypertension. Major risks of any type of transplantation include rejection of the transplanted organ and serious infection, and you must take immunosuppressant drugs for life to help reduce the chance of rejection.