What Is Pulmonary Hypertension: Symptoms, Causes, And Treatment

Pulmonary hypertension is pretty rare, and in the US, only about 1-2 people in every one million¹ have it. Although the disease is life-threatening and worsens over time, treatments can relieve the symptoms and ensure patients have a better life. While that requires some planning, many people with this disease find ways to live their lives and continue doing everything they did before the diagnosis.

What is pulmonary hypertension, and how is it different from hypertension?

Pulmonary hypertension (PH) refers to abnormally high blood pressure in the arteries that carry blood from the heart to the lungs.

The human body has two sets of blood vessels facilitating blood flow from the heart, known as pulmonary circulation and systemic circulation:

• Pulmonary circulation: This set of blood vessels allows the deoxygenated blood to flow from the right side of the heart to the lungs, where it's oxygenated, and then back to the left side of the heart. 

• Systemic circulation: This set facilitates the flow of oxygenated blood from the left side of the heart to the entire body.

Pulmonary circulation normally has lower pressure than systemic circulation. However, if the blood pressure in the pulmonary section increases by an unusually high amount, it results in what is known as pulmonary hypertension.

So, what is the difference between pulmonary hypertension and systemic hypertension? 

• Systemic hypertension results from increased pressure in the arteries throughout the body. 

• Pulmonary hypertension is more specific to the unusual increase in pressure in the arteries that carry blood from the heart to the lungs.

What is pulmonary arterial hypertension?

Pulmonary arterial hypertension (PAH) is a sub-group of pulmonary hypertension and refers to the tightening and stiffening of the walls of the arteries of the lungs. PAH is chronic and currently incurable.

In people with pulmonary arterial diseases, the right side of the heart works harder to pump blood through the narrowed arteries in the lungs. As a result, the right side of the heart enlarges, and its flexibility decreases, affecting its ability to pump blood to the lungs and into the entire body.

Higher pressure in the pulmonary arteries that cause PH does not necessarily mean you have pulmonary arterial hypertension. It may be caused by other diseases such as lung disease, obstructive sleep apnea (OSA), diastolic heart failure, or other reasons altogether. 

What are the symptoms of pulmonary hypertension?

Symptoms of pulmonary hypertension usually begin to show when the condition progresses. So, you may not realize you have pulmonary hypertension in its early stages.

Early symptoms of pulmonary hypertension

• Dizziness

• Bluish lips and skin

• Fatigue

• Fainting spells

• Shortness of breath when you perform daily activities, e.g., climbing stairs

• Swelling in the ankles, abdomen, or legs

• Chest pain

These symptoms range in severity, and you may not necessarily suffer from all of them.

Symptoms of advanced pulmonary hypertension

• Passing out or dizziness

• Irregular heartbeat (palpitations or extreme throbbing sensation)

• Difficulty breathing while at rest

• Tachycardia or racing pulse, where the heartbeat exceeds 100 per minute

• Continuous shortness of breath during exercise or activity

As the condition worsens, you may find it challenging to carry out everyday activities.

What causes pulmonary hypertension?

The underlying conditions that could lead to pulmonary hypertension include:

• Hyperthyroidism – This condition involves the production of excess hormones by the thyroid gland, causing irregular or rapid heartbeat

• Inflamed pulmonary blood vessels

• Chronic lung diseases, including chronic bronchitis and cystic fibrosis

• Recurring blood clot formation in the pulmonary arteries or blood clots that travel from the legs to the pulmonary arteries

• Rheumatologic conditions including lupus, scleroderma (systemic sclerosis), or rheumatoid arthritis

• Use of illicit drugs such as cocaine or methamphetamine

• HIV/AIDS

• Certain heart diseases, including mitral valve disease, aortic valve disease, and congestive heart failure (left side)

• Advanced liver disease

• Low-oxygen conditions such as high altitude living, obstructive sleep apnea, and obesity

• Certain medications, e.g., Fen-Phen medication used for weight loss

How underlying causes lead to pulmonary hypertension

Conditions that interfere with blood flow from the heart to other body parts lead to blood stacking, which causes pulmonary hypertension by increasing pulmonary venous pressure.

This involves:

Changes in blood vessels

Some infections and diseases, including cancer, may cause narrowing of the inner lining of the blood vessels when tissues grow around and within the vessels. Also, scarring and masses from other conditions, like pulmonary fibrosis and sarcoidosis, increase blood pressure by narrowing and compressing blood vessels.

Hypoxic pulmonary vasoconstriction

This refers to lung vessels narrowing as they try to redirect blood flow from the parts of the lungs that are functioning poorly.

For example, pneumonia causes inflammation in part of the lung, affecting its ability to oxygenate and deoxygenate blood. Hypoxic pulmonary vasoconstriction diverts the blood to better functioning areas of the lung that aren’t affected by pneumonia, in an effort to maintain optimum oxygenation. However, this process involves the constriction of the pulmonary artery vessels and raises pulmonary blood pressure.

Blockage of blood vessels

If you have a parasitic infection such as schistosomiasis, it can cause blockages in the blood vessels that lead to pulmonary hypertension.

Constriction of blood vessels

If you take certain substances, including methamphetamines, cocaine, and anti-obesity drugs, e.g., dexfenfluramine (Redux), they may cause constriction of the blood vessels, which elevates blood pressure in the pulmonary artery.

Unclear causes

Some diseases cause pulmonary hypertension for unknown reasons. It is thought, for example, that certain chemical or toxin effects may cause constriction or growth of tissue around or within the vessel.

Classifications of pulmonary hypertension

The World Health Organization (WHO) puts pulmonary hypertension into five groups according to the cause or associated underlying conditions.

Group 1

Pulmonary arterial hypertension (PAH)

Causes:

• Heart problems present during childbirth (congenital heart disease)

• Conditions such as HIV infection, connective tissue disorders (lupus, scleroderma, etc.), and chronic liver disease (cirrhosis)

• Alterations in a gene passed down through generations in a family (heritable PAH)

• Unknown cause (idiopathic PAH)

• Prescription diet medications or illegal drugs, like meth

Group 2

Results from heart disease affecting the right side of the heart

Causes:

• Diseases in the left-sided heart valve, e.g., aortic valve or mitral valve disease

• Failure of the left ventricle

Group 3

Caused by lung disease

Causes:

• Scarred tissues between the lung's air sacs (pulmonary fibrosis)

• Obstructive sleep apnea (OSA)

• Chronic obstructive pulmonary disease (COPD)

• Living in high altitude areas while being at a higher risk of pulmonary hypertension

Group 4

Results from chronic blood clots

Cause:

• Clotting disorders such as chronic blood clotting in the lungs (pulmonary emboli)

Group 5

Triggered by other health conditions

Causes:

• Metabolic disorders, such as glycogen storage disease

• Blood disorders, e.g., essential thrombocythemia and polycythemia vera

• Tumors exerting pressure on the pulmonary arteries

• Kidney disease

• Inflammatory disorders, e.g., vasculitis and sarcoidosis

Potential complications of pulmonary hypertension

Pulmonary hypertension may lead to complications such as:

Arrhythmia

Pulmonary hypertension can lead to irregular heartbeats, resulting in heart palpitations (pounding heartbeat). Sometimes, it may cause dizziness or fainting.

Bleeding in the lungs

Another complication of pulmonary hypertension is bleeding in the lungs. The situation may worsen to the point of coughing up blood (called hemoptysis).

Enlargement of the right ventricles and heart failure

Enlargement of the right ventricles makes the heart pump blood harder than normal as it tries to force the flow through the narrow or blocked arteries. As a result, the heart walls thicken while the right ventricle expands to accommodate more blood. However, the thickening and enlargement creates more strain on the heart, which may ultimately cause heart failure.

Blood clots

People with pulmonary hypertension are at a higher risk of developing blood clots in the small arteries of their lungs.

Pregnancy complications

Pulmonary hypertension puts the mother at risk of severe cardiac outcomes, especially during labor and delivery.

How is pulmonary hypertension diagnosed?

Pulmonary hypertension may result from many medical conditions. Therefore, ruling out the diseases and making the correct diagnosis requires an analysis of your full medical history, physical examination, and symptoms. Below are the physical exams and tests performed to diagnose pulmonary hypertension.

Physical exam

The doctor will complete these processes during a physical exam:

• Establish whether you have abnormal heart sounds, e.g., a loud pulmonic valve sound, a galloping due to ventricular failure, or systolic murmuring of tricuspid regurgitation

• Check for any enlargement or swelling of the jugular vein in the neck

• Look out for fluid retention in the abdomen, legs, and ankles

• Check for a bluish tint to the nail beds

• Examine any signs of other underlying conditions that could be causing pulmonary hypertension

Blood tests

There are several blood tests used in diagnosing pulmonary hypertension. For example:

• Thyroid-stimulating hormone (TSH) test to screen for thyroid problems

• Screening for Human Immunodeficiency Virus (HIV)

• Complete blood count (CBC) test to check for infection, increased hemoglobin, and/or anemia

• B-type natriuretic peptide (BNP) test that is a marker for heart failure

• Arterial blood gases (ABG) test to establish the level of oxygen in arterial blood

• Complete metabolic panel (CMP) test to check liver and kidney function

• Autoantibody blood test, e.g., ANA, ESR, and others, to screen for collagen vascular conditions

Echocardiogram

This test helps understand the likelihood of someone developing pulmonary hypertension. Echocardiogram tests done with a Doppler study help your healthcare provider better understand the pressure in the pulmonary artery. This is a painless ultrasound test that uses high-frequency sound waves to help evaluate blood flow.

Right heart catheterization

The right heart catheterization is a gold-standard test in diagnosing pulmonary hypertension. It involves inserting a catheter via the groin into the femoral vein until it reaches the right side of the heart. The catheter connects to a machine that tracks and measures the blood pressure in the pulmonary arteries and the right side of the heart.

Other tests

• Chest x-rays check for the enlargement of pulmonary arteries and right ventricle.

• A six-minute walk test to determine your tolerance level to exercise and blood oxygen saturation level during the activity

• Pulmonary function test to establish whether there are other lung conditions such as idiopathic pulmonary fibrosis and chronic obstructive pulmonary disease

• Overnight oximetry or polysomnogram test screens for sleep apnea as it leads to reduced oxygen levels at night

• Ventilation-perfusion scan (V/Q scan) test establishes whether there is any blood clotting along the pathway to the lungs.

• Pulmonary angiogram tests screen for blood clots blocking the pulmonary arteries

How is pulmonary hypertension treated?

It is important to obtain the correct pulmonary hypertension diagnosis before commencing any treatment. PH treatment varies by patient, depending on the underlying causes. Adhering to the treatment plan provided by your doctor is the best way to manage pulmonary hypertension.

The general treatments include:

Medication

Several types of medication can treat pulmonary hypertension, and each has a specific goal. The medication prescribed will depend on the underlying causes of the disease, how severe it is, the livelihood it will worsen, and a person’s drug tolerance. 

Diuretics

Diuretics remove excess fluid from the bloodstream and tissues, helping to reduce swelling and enabling easier breathing. Examples include Torsemide (Demadex®), Spironolactone (Aldactone®)], and Furosemide (Lasix®).

Anticoagulants

Also known as blood-thinning drugs, such as Warfarin sodium (Coumadin®), anticoagulants reduce blood clot formation, improving blood flow in the blood vessels. However, people taking blood thinners need to monitor for bleeding complications and undergo regular lab tests to check the level of these drugs in their bloodstream.

Prevention of narrowing blood vessels

Taking Macitentan (Opsumit), Ambrisentan (Letairis®), or Bosentan (Tracleer®) helps counteract the vasoconstriction effects of the protein endothelin. These medications allow the arteries to relax, which lowers pulmonary blood pressure.  If you take Bosentan, you will need monthly lab work to monitor your liver function.

Reduce blood pressure

Certain medications can reduce pulmonary blood pressure and may improve the pumping ability of the right side of the heart. These drugs include Diltiazem (Cardizem®) and Nifedipine (Procardia®).

Relaxation of pulmonary cells

Taking drugs such as Tadalafil (Adcirca®) and Sildenafil (Revatio®) widens the pulmonary arteries by relaxing the pulmonary smooth muscle cells.

Oxygen

Oxygen therapy can help people with low oxygen concentration in their blood.

Blood clot prevention

Medicines such as treprostinil sodium (Orenitram ®, Remodulin®, Tyvaso®), Iloprost (Ventavis®), and Epoprostenol (Veletri, Flolan®) widen pulmonary arteries and prevent blood clots from forming.

Potassium supplements

These can replace the potassium the body loses through increased urination from using diuretics. An example of a potassium drug is K-dur®.

Improve heart pumping

Inotropic agents like Digoxin enhance the heart’s pumping ability.

A quick guide to taking pulmonary hypertension medications

Taking pulmonary hypertension medication requires you to pay close attention to avoid any negative side effects. Ensure you do the following:

• Keep a list of your medications and understand how each of them works

• Avoid quitting a dose or changing your drugs unless you talk with your doctor first

• Avoid taking herbal products alongside medications used for pulmonary hypertension as you may experience some side effects.

• Avoid taking over-the-counter drugs with labels warning those with high blood pressure not to take them. You should ask your doctor before taking any OTC drug. Decongestants such as Sudafed®, Dimetapp®, and Benadryl® or any medications containing pseudoephedrine or ephedrine and non-steroidal anti-inflammatory agents (NSAIDs) such as Indocin®, Motrin®, and Advil® can cause issues in people with heart failure.

• Ensure you take the medications at the same time every day. If you forget a dose, don’t take two doses to compensate for the one you missed, as it’s safer to miss a dose than to potentially overdose. 

Dietary changes

Another way to manage pulmonary hypertension is by making changes to your diet.

Consider making the following dietary changes:

• Switch to foods with high levels of magnesium, e.g., broccoli, peanuts, and tofu, and potassium, e.g., dried fruits, oranges, and bananas

• Limit your daily calorie intake

• Reduce consumption of foods containing cholesterol, refined sugar, and saturated fats

• Eat fiber-rich foods such as fruits, vegetables, whole grains, and bran

• Lower your sodium intake by choosing foods with 'low sodium' or 'low salt' labels, avoid table and seasoning salt, avoid cured, salted, canned, or smoked meat products, and avoid fast food

• Check your fluid intake and reduce it if you notice swelling or realize you are becoming short of breath

• You can also ask the doctor whether you should limit your vitamin K intake. These vitamins are present in some oils and green leafy vegetables and may interfere with how well blood thinners work

Lifestyle changes

Changing your lifestyle can help in managing pulmonary hypertension. Below are some of the lifestyle habits and changes you should consider:

• Avoid shoving, pushing, or lifting items above 20 pounds since they increase pressure in your lungs and arteries. 

• Walking helps improve circulation and maintain strong muscles, but you should avoid strenuous aerobic exercise since your lungs may not sustain the oxygen demands of your body during the activities. Also, stop any activity that causes chest pain, dizziness, or shortness of breath and reach out to your doctor if such symptoms occur.

• Record your weight daily and talk to your doctor if you notice a sudden weight gain of two pounds in a day or five pounds over a week

• If you are overweight, ensure you stick to your doctor's recommendation on weight management.

• Stop smoking

• Reduce or avoid alcohol consumption

• Go for annual health check-ups with your primary care doctor 

• Seek emotional support. Having pulmonary hypertension may cause stress, worry, anxiety, or depression. Share your feelings with your doctor so they can direct you to the help you need, including taking medicine for depression, going for counseling, or joining a patient support group.

Surgical therapies

Below are the surgical interventions that can help manage pulmonary hypertension:

Pulmonary thromboendarterectomy

This surgical therapy involves removing any blood clots to improve blood flow and lung function.

Lung transplant

A lung transplant is an option if advanced pulmonary hypertension doesn’t respond to treatment, as the right side of the heart generally goes back to functioning normally after the procedure. However, the shortage of lung donors is a major barrier to this therapy in the US.

Lung/heart transplant

A lung/heart transplant involves replacing both the heart and the lung. This treatment is rare but necessary for PH patients with lung and left heart failure.

When to see your doctor about pulmonary hypertension?

You should contact your doctor if you experience the following symptoms:

• Shortness of breath that is worsening

• Reduced tolerance for an activity or extreme fatigue with regular activities

• Chest pain episodes

• Confusion or restlessness

• Worsening swelling in the legs, abdomen, and/or legs

• Difficulty breathing at rest or constant lightheadedness or dizziness

• A respiratory infection like a cough that is worsening

• Nausea or poor appetite

• Increased heart rate reaching 120 beats per minute

• Weight gain at a rate of two pounds in a day or five pounds in a week

Patients with pulmonary hypertension generally see cardiologists and pulmonologists (pulmonary physicians). However, other physicians such as rheumatologists, sleep medicine doctors, and infectious disease specialists may be involved, depending on the cause.

Some questions to ask your doctor include:

• What could be the cause of my pulmonary hypertension?

• Which tests will I need, and does insurance cover them?

• Should I limit fluid or salt intake?

• What kind of exercise should I stay away from?

• How often should I visit the doctor for my problem?

• Will treatment of PH interfere with treating other health problems that I have?

• Will I need surgical therapy?

The lowdown

Preventing pulmonary hypertension focuses on reducing the risk factors that lead to the underlying cause. However, some risk factors, such as lupus, are uncontrollable; so, you cannot prevent them. Luckily, early diagnosis and appropriate treatment reduce the chances of advancement of this condition.

If you're diagnosed with pulmonary hypertension, you should have regular follow-ups with your doctor for signs, symptoms, blood pressure, and oxygen level checks. In a nutshell, pulmonary hypertension should be diagnosed and treated early to ensure it does not advance into a life-threatening condition.