Chronic Thromboembolic Pulmonary Hypertension (CTEPH): What Happens?
Medically reviewed by Susan Russell, MD
Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare form of pulmonary hypertension caused by a buildup of blood clots or scar tissue in your lungs. Clotting is a critical process that prevents massive and fatal bleeding, but it can also cause problems with clots developing in the wrong place at the wrong time. A pulmonary embolism is a blood clot that forms in the artery that brings oxygen-rich blood to your lungs.
These clots can cause you immediate problems, but they can also contribute to chronically dangerous complications like thromboembolic diseases.
This article will discuss how chronic thromboembolic disease develops and how it can progress to other complications like chronic thromboembolic pulmonary hypertension.
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When Does Pulmonary Hypertension Become Chronic Thromboembolic Disease?
Pulmonary hypertension is an increase in the pressure in your lungs. Specifically, when the pressure increases, your heart works harder to pump blood into the blood vessels of your lungs. When blood doesn't reach your lungs efficiently, your body has less oxygen, and you can develop symptoms like shortness of breath.
There are several categories of pulmonary hypertension, and they are grouped by the suspected cause of the pressure increase. For perspective, about 1% of people around the world have pulmonary hypertension, and the root cause is unknown for half of them.
The categories for pulmonary hypertension by cause include:
Group 1: Pulmonary arterial hypertension (PAH)
Group 2: Pulmonary hypertension due to left-sided heart disease
Group 3: Pulmonary hypertension due to lung disease and/or hypoxia
Group 4: Pulmonary hypertension due to pulmonary artery obstructions, including chronic thromboembolic pulmonary hypertension
Group 5: Pulmonary hypertension with unknown and/or multiple causes
CTEPH is a rare and progressive form of pulmonary hypertension that usually develops from a pulmonary embolism, a blood clot in one of the arteries leading to the lungs.
Related: Causes and Risk Factors of Pulmonary Embolism
Causes of CTEPH at Each Stage
There are many contributing factors to pulmonary hypertension. In the case of chronic thromboembolic disease, the root cause is typically an acute pulmonary embolism.
A pulmonary embolism occurs when blood clots form in the lungs and block blood flow. Large clots must be treated immediately, but smaller clots may pass and can even go unnoticed. Small, repeated clot formation causes scar tissue to form in the lungs' blood vessels, eventually leading to increased arterial pressure (pulmonary hypertension). Between 0.6% and 4.4% of people who develop a pulmonary embolism later develop CTEPH.
CTEPH Lung, Chest, and Cough Symptoms
CTEPH is considered rare but is also believed to be underdiagnosed. The condition shares symptoms with many other diseases like:
These symptoms may include:
Fatigue
Dizziness or fainting
Palpitations
Related: What Is Idiopathic Pulmonary Fibrosis?
Testing to Diagnose CTEPH
Diagnosing CTEPH is a process. Typically, healthcare providers only diagnose it after a known acute pulmonary embolism (PE). An estimated 75% of people with CTEPH had a confirmed or suspected PE at some point in the past—and CTEPH can develop months or years after the initial clot.
If you are diagnosed with or suspected to have pulmonary hypertension for at least six months after a PE, and the use of anticoagulation medications has ruled out a non-acute blood clot, your healthcare provider may suggest a CTEPH diagnosis.
However, testing to confirm pulmonary hypertension usually comes first. Testing involves a cardiac catheterization and echocardiogram to directly measure the pressure in your pulmonary artery. Once pulmonary hypertension is confirmed, your healthcare team will determine the underlying contributors to create a treatment plan.
If they suspect that PE is the underlying cause, your healthcare provider will order additional testing to make a formal CTEPH diagnosis. These tests include:
A ventilation-perfusion (V/Q) scan to measure how well air and blood move through your lungs
An echocardiogram to check the function of your heart and how hard it is working
Lung function test to measure how well your lungs can hold air and how much tissue is damaged
Right-sided heart catheterization to measure pulmonary artery pressure and determine what type/degree of pulmonary hypertension you have
Pulmonary angiogram to identify blood clots and blocked vessels in your lungs
Magnetic resonance imaging (MRI) for detailed images of clots and structural problems in the body
Exercise tolerance test to measure the degree of symptoms you have over a period of activity, which can include a six-minute walk test or a cardiopulmonary stress test
Related: Pulmonary Embolism Diagnosis: The 3-Step Process
How Pulmonary Hypertension Is Staged
Pulmonary hypertension is staged based on the underlying cause or contributing factors, as listed above. Treatment decisions are based on what group your type of pulmonary hypertension falls into, which include:
Group 1: Treated with lifestyle changes and/or medications to help slow disease progression
Groups 2 and 3: Treatment to address any underlying heart or lung diseases
Group 4: Requires the most extensive forms of treatment, directly removing clots or blockages to relieve pressure (where CTEPH falls)
Surgical Treatment of CTEPH
Surgical treatment is usually the first choice when it comes to treating CTEPH. The preferred surgery in most cases is a pulmonary thromboendarterectomy (PTE) or pulmonary endarterectomy.
This surgery uses a bypass device to redirect blood flow from your heart to a heart-lung bypass machine. While the machine does the work of your heart and lungs, a surgical team works to clear any clots or blockages from your lungs and its associated blood vessels.
This surgery is very effective but highly invasive; not everyone is a candidate. If you can't tolerate the bypass procedure, your healthcare team may offer a somewhat less intense option called balloon pulmonary angioplasty.
With this procedure, a healthcare provider inserts a tiny balloon into your pulmonary artery through a catheter. The balloon is inflated to expand the pulmonary artery. This increases blood flow to reduce the pressure your heart has to overcome to pump blood to the lungs.
If none of these options is viable, a complete lung transplant might be considered—but usually as a last resort.
Learn More: Cardiothoracic Surgery: Everything You Need to Know
Non-Surgical Therapies and Alternatives
Some people with CTEPH and other complex medical issues may not be a candidate for surgical intervention. Other treatment options exist if you can't—or decide not to—pursue surgery, including:
Anticoagulation: Anticoagulation medication is a mainstay for treating CTEPH since most cases result from repeated blood clots. These medications help prevent the formation of additional blood clots that could cause a pulmonary embolism.
Cardiovascular support: Diuretics, anticoagulants, and supplemental oxygen might be used in cases of CTEPH where heart failure or low blood oxygen levels are a significant complication.
Targeted treatment: Riociguat is the only medication specifically approved for CTEPH-related pulmonary hypertension. It works by relaxing blood vessels to reduce pulmonary artery pressure. Other medicines—macitentan (brand name Opsumit) and treprostinil (brand name Orenitram)—may be used off-label. Trials for their use in people with CTEPH are currently underway.
Can CTEPH Be Cured?
People who undergo surgery to remove clots and clear blockages that increase pressure in the pulmonary artery can be cured of CTEPH.
Some factors that may determine if you are a good candidate for PTE surgery are:
Are your blood clots located in arteries that are large enough for surgery?
Are the blood clots accessible by surgery, or are they too distant?
Are you physically strong enough to withstand a major thoracic surgery?
Read Next: Medications for Pulmonary Arterial Hypertension
Ongoing CTEPH Management
Even if you've had surgery to treat CTEPH, you will need to continue taking anticoagulants to help prevent the development of future blood clots and repeated pulmonary emboli.
The use of additional medications and treatments will depend on what other problems you may have developed as a result of CTEPH, like heart failure. Even after successful treatment of CTEPH, you may still need to take medications or receive treatments for problems you developed as a result of your pulmonary hypertension.
Learn More: How to Manage Progressive Pulmonary Hypertension
Life Expectancy With CTEPH
Without treatment, the life expectancy for people with CTEPH is only five years. Without prompt diagnosis and treatment, pulmonary artery pressure will continue to increase. This strains the heart, reducing heart function and causing blood to back up, leading to right-sided heart congestion and strain.
Even if you aren't a candidate for PTE surgery, other treatments like catheter-based interventions and medications can help relieve some pressure and extend your life expectancy.
Summary
CTEPH is a rare and likely underdiagnosed form of pulmonary hypertension that develops from repeated blood clots that form in your lungs. Surgery can cure this condition, but not everyone is a candidate for the intense procedure that's required to clear your lungs of clots and scar tissue.
If you've had a pulmonary embolism, especially if you've experienced shortness of breath for longer than six weeks after being diagnosed with a PE, talk to a healthcare team about long-term follow-up and other steps you can take to reduce your chances of complications like CTEPH.
Read the original article on Verywell Health.
