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What is pulmonary hypertension?
Pulmonary hypertension (PH) is a general diagnosis that means you have high blood pressure in your pulmonary arteries. These are the blood vessels that carry oxygen-poor blood from your heart to your lungs.
Pulmonary hypertension has many different causes. It’s usually a complication of heart disease or lung disease. But many other diseases and environmental factors can raise your risk for PH.
Pulmonary hypertension is dangerous because it disrupts the flow of blood through your heart and lungs. High blood pressure in your pulmonary arteries causes these arteries to become narrow. As a result, your heart must work harder to pump oxygen-poor blood to your lungs.
How does pulmonary hypertension affect my body?
Pulmonary hypertension can cause serious problems in your body, including:
- Anemia.
- Arrhythmias.
- Blood clots in your pulmonary arteries.
- Pericardial effusion.
PH is dangerous for people who are pregnant. It can cause complications for both the birthing parent and fetus.
Without treatment, pulmonary hypertension can overtax your heart and eventually be fatal. High blood pressure in your pulmonary arteries forces your heart to work harder to send oxygen-poor blood to your lungs. Your right ventricle (lower right chamber) is responsible for pumping this blood to your lungs. So, over time, PH causes your right ventricle to get bigger due to the extra work. This condition (right ventricular hypertrophy) can lead to right-sided heart failure.
Right-sided heart failure has a ripple effect throughout your body. It can disrupt the normal workings of many organs and systems.
What are the different types of pulmonary hypertension?
Group 1: Pulmonary Arterial Hypertension (PAH)
WHO Group 1 refers to pulmonary arterial hypertension (PAH), which is caused when the arteries in the lungs become narrowed, thickened or stiff. The right side of the heart must work harder to push blood through these narrowed arteries. This extra stress can cause the heart to lose its ability to pump enough blood through the lungs to meet the needs of the rest of the body.
Group 2: Pulmonary Hypertension Due to Left Heart Disease
WHO Group 2 includes PH due to left heart disease. In this group of PH, the arteries and lungs are not as thick or stiff as WHO Group 1, but there are problems with how the heart squeezes or relaxes, or problems with the valves on the left side of the heart. Because of this, the left heart is unable to keep up with the blood returning from the lungs — causing a “backup” of blood which raises pressure in the lungs. WHO Group 2 is the most common form of PH.
Group 3: Pulmonary Hypertension Due to Lung Disease
WHO Group 3 includes PH due to chronic lung disease and/or hypoxia (low oxygen levels). These lung diseases include obstructive lung disease where the lung airways narrow and make it harder to exhale (e.g. COPD or emphysema); restrictive lung disease in which the lungs have a tough time expanding when one inhales (e.g. interstitial lung disease or pulmonary fibrosis); sleep apnea; and living in an area of high altitude for a long period of time. Arteries in the lungs tighten so that blood can only go to areas of the lungs that are receiving the most air and oxygen. This tightening leads to high blood pressure throughout the lungs.
Group 4: Pulmonary Hypertension Due to Chronic Blood Clots in the Lungs
WHO Group 4 is called chronic thromboembolic pulmonary hypertension (CTEPH). CTEPH can occur when the body is not able to dissolve a blood clot in the lungs. This can lead to scar tissue in the blood vessels of the lungs, which blocks normal blood flow and makes the right side of the heart work harder. This type of PH is unique because it can potentially be cured through pulmonary thromboendarterectomy (PTE) surgery to remove the blood clots. However, not all CTEPH patients are eligible for this surgery. A drug is also available for CTEPH patients if a doctor determines that a patient is not a candidate for the PTE surgery or if PH remains after the surgery.
Group 5: Pulmonary Hypertension Due to Unknown Causes
WHO Group 5 is where PH is secondary to other diseases in ways that are not well understood. These associated conditions include, but are not limited to, sarcoidosis, sickle cell anemia, chronic hemolytic anemia, splenectomy (spleen removal) and certain metabolic disorders.
Who does pulmonary hypertension affect?
Pulmonary hypertension is high blood pressure in the arteries of the lungs. It is a rare, progressive disease affecting people of all ages.
Children are either born with narrowing in the lung arteries or the arteries become thicker and narrower over time. The narrowing in the arteries causes increased pressure. The right ventricle pumps blood to the lungs to receive oxygen. In pulmonary arterial hypertension, a type of pulmonary hypertension, the right ventricle needs to pump against the increased pressure in the lung arteries. This can lead to heart problems over time, especially with the right ventricle. The walls of the right ventricle can become much thicker than normal, and the function of the right ventricle can decrease over time.
How common is pulmonary hypertension?
Primary pulmonary hypertension (PPH) is a rare lung disorder that causes high blood pressure in the lungs.
Some forms of pulmonary hypertension are linked to a gene defect that can run in families. Researchers believe this gene mutation makes the blood vessels more sensitive to certain factors and they constrict, or narrow, when exposed to these factors.
What are the stages of pulmonary hypertension?
Pulmonary hypertension is divided into four stages based on the severity of symptoms.
These stages are based on criteria established by the World Health Organization (WHO)Trusted Source:
- Class 1. The condition doesn’t limit your physical activity. You don’t experience any noticeable symptoms during periods of ordinary physical activity or rest.
- Class 2. The condition slightly limits your physical activity. You experience noticeable symptoms during periods of ordinary physical activity, but not during periods of rest.
- Class 3. The condition significantly limits your physical activity. You experience symptoms during periods of slight physical exertion and ordinary physical activity, but not during periods of rest.
- Class 4. You’re unable to carry out any type of physical activity without symptoms. You experience noticeable symptoms, even during periods of rest. Signs of right-sided heart failure tend to occur in this stage.
What causes pulmonary hypertension?
Sometimes doctors can’t find a reason for high blood pressure in the lungs. In that case, the condition is called idiopathic pulmonary hypertension. Genes may play a role in why some people get it.
In other cases, there is another condition that’s causing the problem. Any of these illnesses can lead to high blood pressure in your lungs:
- Congestive heart failure
- Blood clots in the lungs
- HIV
- Illegal drug use (like cocaine or methamphetamine)
- Liver disease (such as cirrhosis of the liver)
- Lupus, scleroderma, rheumatoid arthritis, and other autoimmune diseases
- A heart defect you’re born with
- Lung diseases like emphysema, chronic bronchitis, or pulmonary fibrosis
- Sleep apnea
What is the treatment for pulmonary hypertension?
Pulmonary hypertension treatment depends on the type of PH you have and your other medical conditions. Your healthcare team will tailor treatment to your individual needs.
Right now, only two types of PH can be treated directly:
- Pulmonary artery hypertension (PAH).
- Chronic thromboembolic pulmonary hypertension (CTEPH).
Treatment for other types of PH involves managing the underlying medical conditions.
Treatment for pulmonary arterial hypertension (PAH) includes:
- Calcium channel blockers. These medications can help lower the blood pressure in your pulmonary arteries and throughout your body.
- Diuretics. These “water pills” help your body clear out extra fluid.
- Oxygen therapy. You may need this treatment if you don’t have enough oxygen in your blood.
- Pulmonary vasodilators. These medications help your pulmonary arteries relax and open up better. This improves blood flow and lowers the strain on your heart.
Treatment for CTEPH includes:
- Anticoagulants. These medicines help prevent blood clots.
- Balloon atrial septostomy (BAS). This procedure is typically used for babies with critical heart defects. However, it’s also used for adults with pulmonary hypertension. It’s a bridge that helps keep you stable as you wait for a lung transplant.
- Balloon pulmonary angioplasty (BPA). This catheter-based procedure uses a balloon to widen your pulmonary artery. It’s usually done if you can’t have open surgery.
- Medication. A soluble guanylate cyclase stimulator (SGCS) may help slow down the disease progression.
- Pulmonary endarterectomy (PEA). This surgery removes blood clots from your lungs. It’s currently the only possible cure for pulmonary hypertension, and it’s only for people with CTEPH.