Chronic thromboembolic pulmonary hypertension is a long-term form of high blood pressure in the lungs caused by old blood clots that do not fully clear. People with this condition often feel short of breath, tired, and lightheaded, especially with activity. It can affect adults of any age, and early symptoms of chronic thromboembolic pulmonary hypertension may be mild and mistaken for low fitness. Without treatment it can worsen over time, but many people do well with specialized care. Treatment can include blood thinners, targeted lung-pressure medicines, balloon angioplasty, or surgery to remove clot material, and survival improves with the right treatment plan.
Overview
Chronic thromboembolic pulmonary hypertensionSymptoms
Chronic thromboembolic pulmonary hypertension causes breathlessness with activity, fatigue, and reduced stamina. People may notice chest discomfort, racing heartbeat, dizziness or fainting, and ankle swelling. Early symptoms of chronic thromboembolic pulmonary hypertension can be subtle and mistaken for deconditioning.
Outlook and prognosis
Many people with chronic thromboembolic pulmonary hypertension improve meaningfully with timely diagnosis and specialized care. Procedures like pulmonary endarterectomy or balloon angioplasty, along with tailored medicines and rehab, can lower pressure, boost stamina, and extend survival. Outcomes vary by clot location, heart strain, and other health conditions.
Causes and risk factors
Chronic thromboembolic pulmonary hypertension usually follows unresolved lung blood clots after pulmonary embolism or deep‑vein thrombosis. Risks include prior clots, clotting disorders (inherited/acquired), cancer, splenectomy, chronic inflammation, catheters, infections. Surgery, immobility, travel, pregnancy, estrogen therapy, and obesity raise risk.
Genetic influences
Genetics play a limited role in chronic thromboembolic pulmonary hypertension. Most cases follow a prior, often unrecognized, blood clot rather than inherited changes. Rare variants affecting clotting or vessel remodeling may slightly raise risk but aren’t primary drivers.
Diagnosis
Doctors start with your history, exam, and an echocardiogram, then screen with a ventilation–perfusion (V/Q) scan. CT pulmonary angiography and right heart catheterization confirm the diagnosis of Chronic thromboembolic pulmonary hypertension and measure pressures.
Treatment and drugs
Treatment for chronic thromboembolic pulmonary hypertension focuses on improving blood flow, easing strain on the right heart, and supporting daily activity. Options may include lifelong anticoagulation, targeted pulmonary hypertension medicines, oxygen, and supervised exercise. Many benefit from surgery or balloon pulmonary angioplasty to remove or open clots.
Symptoms
Chronic thromboembolic pulmonary hypertension can make everyday activities feel unusually taxing, especially anything that gets your heart rate up. Early symptoms of chronic thromboembolic pulmonary hypertension are often subtle—getting winded on a short staircase or needing more time to recover after a brisk walk. You might notice small changes at first. For some, these problems build slowly and differ from person to person.
Breathlessness with activity is the most common symptom. It may start with exertion like climbing stairs or walking uphill and can progress to breathlessness at rest. In chronic thromboembolic pulmonary hypertension, blocked lung vessels make it harder to move oxygen during effort.
You may feel unusually tired or heavy-legged after routine tasks. What once felt effortless can start to require more energy or focus. Rest may help only a little.
Chest pressure, tightness, or pain can appear during exertion. It happens as the right side of the heart works harder to push blood through narrowed lung vessels. If chest pain is severe or sudden, seek urgent care.
Lightheadedness, near-fainting, or fainting can occur, especially with activity. In chronic thromboembolic pulmonary hypertension, limited blood flow can drop blood pressure during exertion. If you pass out, get medical help promptly.
How people usually first notice Chronic thromboembolic pulmonary hypertension?
Many people first notice chronic thromboembolic pulmonary hypertension (CTEPH) after a pulmonary embolism when breathlessness, fatigue, or reduced exercise tolerance never fully return to baseline over weeks to months. The first signs of chronic thromboembolic pulmonary hypertension often include persistent shortness of breath on exertion, lightheadedness, chest discomfort, or swollen ankles, which may be mistaken for deconditioning or asthma, and some notice a slow, unexplained decline in stamina. Doctors usually first suspect it when symptoms linger after anticoagulation for a prior clot, or when tests show mismatched ventilation–perfusion scans or signs of strain on the right side of the heart.
Types of Chronic thromboembolic pulmonary hypertension
Chronic thromboembolic pulmonary hypertension (CTEPH) can show up in a few recognizable patterns that affect daily stamina, breathlessness, and how your heart and lungs cope over time. Some people mainly notice shortness of breath when walking up stairs or carrying groceries, while others feel chest pressure, lightheadedness, or swelling in the legs. Clinicians often describe them in these categories: how far the disease has progressed, how the clots are distributed in the lung arteries, and how well the right side of the heart is functioning. Not everyone will experience every type, and the balance of symptoms can shift over time.
Functional class I–II
Symptoms are absent at rest and appear with moderate to heavier activity. People may notice breathlessness on hills, stairs, or brisk walks but manage everyday tasks. Early symptoms of CTEPH can be subtle and easy to overlook.
Functional class III
Symptoms appear with light activity, like slow walking on flat ground or dressing. Fatigue and shortness of breath limit daily routines and errands. Swelling in the ankles may come and go.
Functional class IV
Symptoms occur even at rest or with minimal movement. Breathlessness, chest pressure, and near-fainting spells can be prominent. Legs and abdomen may swell as the right heart struggles.
Proximal disease
Larger clots and scar tissue are mainly in the main or lobar lung arteries. Shortness of breath can be marked, but surgery to remove the blockages may be an option. Recovery of exercise capacity can be substantial after successful treatment.
Distal disease
Narrowing is mostly in the smaller, segmental or subsegmental arteries. Symptoms often include exercise intolerance and early fatigue. Balloon procedures or medications may be used if surgery is not feasible.
With chronic PEa syndrome
People have persistent breathlessness after a past pulmonary embolism but no clear resting pulmonary hypertension. Symptoms typically show up with exertion, and testing may reveal abnormal exercise responses. This pattern can progress, so follow-up is important.
Right-heart strain predominant
The right side of the heart is under higher pressure and starts to weaken. People may notice swelling, rapid heartbeat, or faintness along with breathlessness. Fluid retention can require careful monitoring of salt and fluids.
Residual PH after treatment
Some have ongoing pulmonary hypertension after surgery or balloon angioplasty. Symptoms may improve but not fully resolve, leading to limits with exertion. Medications and rehabilitation can help maximize activity levels.
What genetics can tell you about symptoms
Some people with chronic thromboembolic pulmonary hypertension carry thrombophilia variants like factor V Leiden or prothrombin G20210A, which raise the chance of forming clots that can later scar and narrow lung arteries. This scarring increases pressure in those vessels, driving breathlessness and fatigue.
Causes and risk factors
It often starts when a blood clot in the lungs does not fully clear and becomes scar tissue.
Risk factors for chronic thromboembolic pulmonary hypertension include a prior pulmonary embolism or repeated clots.
Medical factors like cancer, autoimmune clotting disorders, or a past splenectomy can raise risk.
Doctors distinguish between risk factors you can change and those you can’t.
Long immobility during travel or after surgery and estrogen therapy can raise clot risk, and family history or some inherited traits can also increase the chance of chronic thromboembolic pulmonary hypertension.
Environmental and biological risk factors
Chronic thromboembolic pulmonary hypertension (CTEPH) can develop when clots in the lung arteries don’t fully dissolve and instead turn into scar-like blockages that raise pressure. Understanding the biological and environmental factors that increase this risk can help you act early if symptoms start to appear. Doctors often group risks into internal (biological) and external (environmental). Knowing these factors can guide you to seek care if early symptoms of chronic thromboembolic pulmonary hypertension arise.
Having had a clot travel to the lungs raises the chance that some blockage remains behind. Residual blockage can harden over time and drive up pressure in the lung arteries.
A big or widespread initial clot damages more vessels and leaves more material to scar. This increases strain on the lung circulation and the likelihood of CTEPH.
New clots arriving after an earlier event layer additional blockage onto old scar. Over time this stacking effect narrows arteries and increases pulmonary pressure.
When the body clears clots slowly, leftover material can organize into tough tissue. These changes make it harder for blood to flow through the lungs.
Genetic risk factors
Genetics seem to play a smaller role in Chronic thromboembolic pulmonary hypertension (CTEPH) than in some other clotting conditions, but a few inherited traits may affect risk. Carrying certain risks doesn’t automatically lead to CTEPH, yet knowing about them can guide conversations with your care team. Below are the most studied genetic risk factors for chronic thromboembolic pulmonary hypertension. Most people with CTEPH do not have a single, clear-cut inherited cause.
Limited genetic contribution: Genetics appear to play a modest role in CTEPH. Most people have no identifiable inherited cause.
Non-O blood group: People with A, B, or AB blood types tend to have higher levels of certain clotting proteins, which can raise clot risk. Studies suggest non-O blood groups appear more often in CTEPH than expected, though blood type alone is not predictive.
Inherited clotting disorders: Changes like factor V Leiden or the prothrombin gene variant can make blood clots more likely. Their link to CTEPH is weaker and less consistent than their link to deep vein thrombosis or pulmonary embolism.
Fibrinogen gene changes: Certain changes in the fibrinogen A alpha chain can make clots tougher to break down. Some research finds these variants more often in CTEPH, but they are not routinely tested in clinics.
Family history clues: Relatives with unprovoked blood clots can signal an inherited tendency to clot. This background may increase the chance that a pulmonary embolism persists and leads to CTEPH, but it does not determine the outcome.
Lifestyle risk factors
Lifestyle choices can influence symptoms, exercise capacity, and complications in Chronic thromboembolic pulmonary hypertension. Here are practical lifestyle risk factors for Chronic thromboembolic pulmonary hypertension to consider alongside medical care. These focus on day‑to‑day habits that can meaningfully affect breathlessness, swelling, and clot risk.
Regular, moderate activity can improve exercise capacity and reduce breathlessness in CTEPH. Sudden, intense exertion may trigger symptoms; structured pulmonary or cardiac rehab is often safer.
Long periods of sitting slow leg blood flow and raise the chance of new clots that can worsen CTEPH. Standing and brief walks every hour help maintain circulation.
Excess sodium promotes fluid retention, leg swelling, and right-heart strain in CTEPH. Choosing lower-salt foods can ease congestion and shortness of breath.
Large, rapid fluid intakes can worsen edema and abdominal fullness in CTEPH-related right-heart dysfunction. Following individualized fluid targets helps control symptoms.
Risk prevention
Chronic thromboembolic pulmonary hypertension (CTEPH) can sometimes develop after a blood clot in the lungs that doesn’t fully clear. The best way to lower risk is to prevent clots, treat any pulmonary embolism promptly, and follow up if breathing doesn’t return to normal. Knowing your risks can guide which preventive steps matter most. Regular care helps catch problems early so treatment can start before pressure builds in the lungs.
Quick diagnosis and full treatment of a pulmonary embolism lowers the chance of lingering clots. If breathing or stamina don’t bounce back after treatment, ask about evaluation for CTEPH. Early follow-up reduces long-term strain on the heart.
Take blood thinners exactly as prescribed and don’t skip doses. Missing medication can let new clots form and raise the risk of CTEPH. Check for drug interactions and keep INR in range if you use warfarin.
If shortness of breath or fatigue persists 3 months after a PE, request reassessment. Ask whether an echocardiogram and a ventilation–perfusion (V/Q) scan are appropriate to look for CTEPH. Early symptoms of chronic thromboembolic pulmonary hypertension can be subtle, like breathlessness on stairs.
If CTEPH is suspected, seek a center experienced in pulmonary hypertension. Expertise improves detection and guides options like surgery or catheter procedures if needed. Coordinated care helps prevent complications.
Transmission
Chronic thromboembolic pulmonary hypertension (CTEPH) is not contagious; it cannot be passed from one person to another through touch, air, or blood. It develops over time when blood clots in the lungs do not fully clear and turn into scar-like blockages that raise pressure in the lung blood vessels. CTEPH itself is not usually inherited, and there is no known genetic transmission of chronic thromboembolic pulmonary hypertension, though some people may have inherited clotting tendencies that raise the risk of the initial blood clots. Because there is no person-to-person transmission, there is no “infectiousness” to measure.
When to test your genes
Chronic thromboembolic pulmonary hypertension is usually not genetic, so routine genetic testing isn’t needed. Consider testing if you have unexplained or recurrent blood clots, a strong family history of clotting or pulmonary hypertension, or develop CTEPH at a young age. Results can guide anticoagulation choices and screening for relatives.
Diagnosis
Climbing stairs that used to be easy now leaves you short of breath, or you notice ankle swelling by evening—these everyday changes often prompt evaluation for Chronic thromboembolic pulmonary hypertension. Doctors usually piece together clues from your history, an exam, heart and lung imaging, and pressure measurements. Tests may feel repetitive, but each one helps rule out different causes. The diagnosis of Chronic thromboembolic pulmonary hypertension is confirmed by a combination of imaging that shows old clots and a heart catheterization that documents high pressure in the lung arteries.
Your provider asks about prior blood clots, surgery, or long immobilization and reviews symptoms like breathlessness and fatigue. They listen to the heart and lungs and check for leg swelling or signs of right heart strain.
An ultrasound of the heart estimates pressure in the lung arteries and looks for right heart enlargement or weakened pumping. It suggests pulmonary hypertension and guides which tests come next.
A ventilation–perfusion scan compares airflow and blood flow in the lungs to spot mismatched areas typical of chronic clots. It is the preferred screening test for CTEPH, and a normal result makes CTEPH very unlikely.
A contrast CT shows detailed pictures of the lung arteries to find webs, bands, or blockages from old clots. It can also reveal other lung or vessel problems and helps assess anatomy for surgery or angioplasty.
Stages of Chronic thromboembolic pulmonary hypertension
Chronic thromboembolic pulmonary hypertension (CTEPH) is staged by how much symptoms limit everyday activities, using the World Health Organization (WHO) functional class I–IV. These stages focus on what you feel with activity—mainly breathlessness, fatigue, chest pressure, or lightheadedness. Many people feel reassured knowing what their tests can—and can’t—show. Doctors usually check your stage during visits by asking about daily activities, reviewing vital signs, and using simple tests like a walking test or an ultrasound of the heart (echo).
Class I
You have no symptoms with routine daily activity. Early symptoms of chronic thromboembolic pulmonary hypertension may show up only with strenuous exercise.
Class II
You have mild shortness of breath or fatigue with ordinary activity like brisk walking or climbing a flight of stairs. Rest usually brings quick relief. Daily tasks are mostly manageable but feel harder than before.
Class III
You feel breathless or tired with less-than-usual activity, such as showering or carrying groceries. You may need to pause often to catch your breath. Work and household chores can become challenging.
Class IV
Symptoms are present even at rest, and any activity increases discomfort. Breathlessness, chest pressure, or lightheadedness can be significant. Swelling in the legs or ankles and bluish lips are signs your doctor may look for.
Outlook and prognosis
Breathlessness walking up a flight of stairs, swollen ankles by evening, or needing more time to recover after a cold—these day-to-day changes often shape how people with Chronic thromboembolic pulmonary hypertension (CTEPH) judge their progress. The outlook is not the same for everyone, but steady treatment can improve stamina, protect the heart, and reduce flare-ups. Understanding the prognosis can guide planning and help you and your care team decide when to use medicines, balloon pulmonary angioplasty (BPA), or surgery.
Here’s what research and experience suggest about the future. Without treatment, CTEPH can strain the right side of the heart and may shorten life; with expert care, survival improves markedly, especially after successful pulmonary endarterectomy (PEA) surgery, which can be curative for many. When PEA isn’t an option, repeated BPA procedures plus targeted medications often relieve symptoms and raise exercise capacity. Some people experience long stretches of stable breathing and activity, while others notice gradual limits that require stepwise changes in therapy. Early care can make a real difference, since treating elevated lung pressures sooner helps prevent permanent heart damage and reduces hospital stays. For those wondering about early symptoms of CTEPH that signal worsening—rising breathlessness, new leg swelling, fainting spells, or chest pressure—seek prompt evaluation.
Long term, most people with CTEPH can maintain daily routines with the right mix of care, though some will need oxygen or ongoing medications. In medical terms, the long-term outlook is often shaped by both genetics and lifestyle, as well as the location and amount of chronic clot and how the right heart adapts. Talk with your doctor about what your personal outlook might look like, including whether surgical or catheter-based options apply to your situation and how they affect survival and quality of life.
Long-term effects
Chronic thromboembolic pulmonary hypertension can change how far you can walk, how deeply you breathe, and how much energy you have day to day. Long-term effects vary widely, depending on how much pressure builds in the lung arteries and how the right side of the heart adapts. Early symptoms of chronic thromboembolic pulmonary hypertension can be subtle, but over time the condition can lead to lasting limits in stamina and heart strain. Effective treatments, including surgery or catheter procedures, may ease symptoms and improve outlook, though some effects can persist.
Shortness of breath can linger, especially with stairs or hills. Tiredness often follows routine tasks and may fluctuate from day to day.
Stamina tends to drop over time, making walks or chores feel harder. Many people pace activities and plan extra time for recovery.
High pressure in the lung arteries makes the right side of the heart work harder. Over years, it can enlarge and weaken, leading to right-sided heart failure.
Fluid can build up in the ankles, legs, or abdomen. Shoes may feel tight by evening, and rings or waistbands may feel snug.
How is it to live with Chronic thromboembolic pulmonary hypertension?
Living with chronic thromboembolic pulmonary hypertension often means pacing your day around your breathing and energy, with tasks that once felt routine—climbing stairs, carrying groceries, keeping up a conversation while walking—now requiring breaks and planning. Many notice swelling in the legs, chest tightness, lightheadedness, or a racing heartbeat with exertion, and the unpredictability of “good” versus “hard” days can make work, travel, and social plans more complex. Treatments, oxygen use, and regular monitoring add structure to life, and loved ones may take on more practical support, but they also become partners in noticing symptoms early, adjusting activities, and celebrating steadier stretches. With a care team, pulmonary rehab, and clear communication at home, many find a new rhythm that protects health while keeping important parts of life in reach.
Treatment and drugs
Treatment for chronic thromboembolic pulmonary hypertension (CTEPH) focuses on lowering pressure in the lung arteries, improving oxygen levels, and, when possible, removing the clots that cause the problem. For many people, the most effective option is pulmonary endarterectomy surgery, which clears old, organized clots from the lung arteries and can greatly improve breathing and exercise capacity; when surgery isn’t possible, a catheter procedure called balloon pulmonary angioplasty may widen narrowed vessels. Medicines that relax the lung arteries, such as riociguat and sometimes other pulmonary hypertension drugs, can ease symptoms and improve walking distance, and oxygen therapy or diuretics may be added to support day-to-day comfort. Anticoagulants (blood thinners) are usually recommended long-term to prevent new clots from forming, and a doctor may adjust your dose to balance benefits and side effects. Although living with CTEPH can feel overwhelming, many people manage their symptoms and live fulfilling lives with a tailored plan that often combines procedures, medicines, and regular follow-up at a specialized center.
Non-drug treatment
Non-drug care can make day-to-day breathing and stamina better, even when symptoms feel stubborn. Alongside medicines, non-drug therapies can improve how far you can walk, your oxygen levels, and overall quality of life. Because early symptoms of Chronic thromboembolic pulmonary hypertension can be subtle, many reach care once breathlessness limits routines—but these options can help at any stage. Your team will tailor choices based on whether your clots are operable, your lung pressures, and your goals.
A specialist removes old clot tissue from the lung arteries to lower pressures and ease strain on the heart. For many, this is the most definitive option with the potential for long-term relief. Careful preoperative assessment decides if surgery is suitable.
A tiny balloon is threaded into narrowed lung arteries and gently inflated to improve blood flow. It is done in stages for people who are not surgical candidates or have residual blockages. Recovery is usually quick, with monitoring for lung irritation.
Supervised exercise, breathing training, and education help you build strength safely. Programs adjust pacing, intensity, and rest to your oxygen needs. Ask your doctor which non-drug options might be most effective for your current activity level.
Extra oxygen can ease breathlessness and protect organs when levels dip, including during sleep or activity. Your team will set targets and advise how and when to use it. Portable systems can support work, errands, and travel.
Your genes may have an impact on how drugs work for you
Genes can influence how your body processes blood thinners, diuretics, and pulmonary vasodilators for chronic thromboembolic pulmonary hypertension, affecting dose needs and side‑effect risk. Pharmacogenetic testing and careful monitoring help tailor treatment so it’s safer and more effective.
Pharmacological treatments
Medicines can help lower lung blood pressure, improve stamina, and relieve swelling and breathlessness after diagnosis. Understanding early symptoms of chronic thromboembolic pulmonary hypertension can speed evaluation, but once identified, treatment is tailored to whether surgery or angioplasty is possible. First-line medications are those doctors usually try first, based on how well they’re proven to work and a person’s overall health. Your care team will adjust drugs over time to fit your response and limit side effects.
This is the only approved drug for inoperable or persistent CTEPH after surgery, and it helps relax lung blood vessels. It can improve walk distance and quality of life. Dosing may be increased or lowered gradually to balance benefits and side effects.
Warfarin or direct oral anticoagulants (apixaban, rivaroxaban, dabigatran, edoxaban) help prevent new clots from forming. Most people with CTEPH need lifelong anticoagulation unless there’s a strong reason not to. Warfarin requires regular blood tests, while DOACs usually do not.
Bosentan, ambrisentan, or macitentan may be used off-label when surgery or angioplasty isn’t possible or symptoms persist. These drugs relax lung arteries and can improve exercise capacity. Liver monitoring and strict pregnancy precautions are important.
Sildenafil or tadalafil are sometimes used off-label to lower pressure in lung arteries when riociguat isn’t suitable. They may boost exercise tolerance and ease shortness of breath. Avoid combining them with nitrates due to unsafe blood pressure drops.
Genetic influences
Genetics does not appear to be the main driver of chronic thromboembolic pulmonary hypertension (CTEPH), and most cases are not inherited. It’s natural to ask whether family history plays a role. Many people who develop CTEPH have had a prior blood clot in the lung that doesn’t fully clear; inherited tendencies to form clots can raise the chance of having those clots, but the link between these traits and actually developing CTEPH is modest and not consistent across studies. One of the clearer signals is blood type: people with non‑O types, especially type A, seem to have a higher risk. Rare families with more than one person affected have been described, yet a simple, predictable inheritance pattern hasn’t been shown, and having a relative with CTEPH doesn’t mean you will develop it. Doctors may discuss checking for inherited clotting traits when clots occur at a young age or without a clear trigger; understanding potential genetic risk factors for chronic thromboembolic pulmonary hypertension can help guide prevention and family conversations.
Is Chronic thromboembolic pulmonary hypertension genetic?
Genetics play a limited role in chronic thromboembolic pulmonary hypertension. Most cases follow a prior, often unrecognized, blood clot rather than inherited changes. Rare variants affecting clotting or vessel remodeling may slightly raise risk but aren’t primary drivers.
Pharmacogenetics—how genetics influence drug effects
For people with Chronic thromboembolic pulmonary hypertension (CTEPH), treatment often includes lifelong blood thinners and sometimes medicines like riociguat to lower pressure in the lung arteries; genes can affect how some of these drugs work or what dose is safest. Genetic testing can sometimes identify how your body breaks down warfarin, which helps your doctor choose a safer starting dose and adjust it more precisely. Certain inherited differences in the genes involved in processing warfarin or in its drug target can make someone need a lower or higher dose and may raise bleeding risk if dosing isn’t tailored. For newer blood thinners such as apixaban or rivaroxaban, routine genetic testing isn’t recommended today; kidney function, age, body weight, and other medicines usually matter more. For riociguat and other pulmonary hypertension therapies used in CTEPH, there’s no clear evidence that genetics should guide everyday dosing, though smoking status, liver or kidney disease, and drug interactions can change levels. In practice, pharmacogenetic testing for chronic thromboembolic pulmonary hypertension is most useful when warfarin is prescribed, while other parts of care are tailored more by your overall health and response.
Interactions with other conditions
People living with chronic lung disease, like COPD or sleep apnea, often notice their breathlessness and fatigue are worse if chronic thromboembolic pulmonary hypertension is also in the picture. Doctors call it a “comorbidity” when two conditions occur together. Chronic thromboembolic pulmonary hypertension frequently overlaps with a history of blood clots in the legs or lungs and with clotting tendencies such as antiphospholipid syndrome; prior splenectomy and certain blood disorders have also been linked to a higher risk. Thyroid problems and obesity can add strain on the heart and lungs, and untreated sleep apnea may raise pressures in the lung arteries, making symptoms tougher to control.
When heart or kidney disease is present, fluid buildup and reduced exercise tolerance can intensify, and adjusting diuretics or other medicines may be necessary. Cancer and recent surgery can complicate anticoagulation, while some medications may interact with blood thinners used for chronic thromboembolic pulmonary hypertension. If procedures like pulmonary endarterectomy or balloon angioplasty are being considered, other illnesses can influence timing, anesthesia risk, and recovery. Talk with your doctor about how your conditions may influence each other so your care plan balances clot prevention, symptom relief, and safety.
How genes can cause diseases
Humans have more than 20,000 genes, each carrying out one or a few specific functions in the body. One gene instructs the body to digest lactose from milk, another tells the body how to build strong bones and another prevents the body's cells from beginning to multiply uncontrollably and developing into cancer. As all of these genes combined are the building instructions for our body, a defect in one of these genes can have severe health consequences.
Through decades of genetic research, we know the genetic code of any healthy/functional human gene. We have also identified that in certain positions on a gene, some individuals may have a different genetic letter from the one you have. We call these hotspots "Genetic Variations" or "Variants" in short. In many cases, studies have been able to show that having the genetic letter "G" in the position makes you healthy, but having the letter "A" in the same position disrupts the gene function and causes a disease. Genopedia allows you to view these variants in genes and summarizes all that we know from scientific research, which genetic letters (Genotype) have good or bad consequences on your health or on your traits.
History
Throughout history, people have described sudden breathlessness after a serious lung clot, then months later finding they still couldn’t climb stairs without stopping. Doctors noticed that for some, recovery never fully came, and lingering strain on the right side of the heart set in. Families and communities once noticed patterns: someone who had a “clot in the lung” remained winded long after the hospital stay and developed swelling in the ankles by evening.
First described in the medical literature as a long-term consequence of pulmonary embolism, chronic thromboembolic pulmonary hypertension (CTEPH) slowly came into focus over the 20th century. Early on, it was recognized mainly at surgery or autopsy, when old, organized clots were found stuck to the lung’s blood vessels. Clinicians began to link these findings with years of breathlessness, lightheadedness on exertion, and fatigue that didn’t match a person’s age or activity level.
As medical science evolved, imaging changed the story. Chest X‑rays hinted at enlarged pulmonary arteries, but ventilation–perfusion scans in the 1960s and 1970s showed clear “perfusion defects” that didn’t go away, pointing to blocked vessels. Later, right heart catheterization made it possible to measure high pressure in the lung circulation directly, confirming pulmonary hypertension in people whose symptoms persisted after a pulmonary embolism. Over time, descriptions became more precise, separating CTEPH from other types of pulmonary hypertension and from asthma, deconditioning, or anxiety, which can feel similar early on.
Surgery transformed outlooks. In the late 20th century, specialized centers refined pulmonary endarterectomy, a delicate operation to remove old clot material from deep within the lungs’ arteries. Many living with CTEPH who underwent this surgery saw pressures drop and stamina return, shifting the condition from a progressive, often fatal problem to one that can be treatable or even curable in the right candidates. For those with disease in smaller vessels or who weren’t surgical candidates, balloon pulmonary angioplasty emerged more recently, opening narrowed branches and improving symptoms step by step.
Advances in genetics and clotting research also shaped understanding. While CTEPH is not typically inherited, studies uncovered risk factors like certain blood clotting tendencies, spleen removal, chronic infections, and long-term catheters. Awareness grew that not everyone with a pulmonary embolism develops CTEPH, and that early follow-up matters when breathlessness lingers beyond three months.
In recent decades, awareness has grown, and with it, new medicines that relax lung vessels or target the vessel wall have been tested and approved to help people who are not surgical candidates or who have residual pulmonary hypertension after surgery. Today, the history of CTEPH is a story of sharper diagnosis, effective interventions, and coordinated care in expert centers. Looking back helps explain why persistent symptoms after a pulmonary embolism should prompt evaluation, and why timely referral can change the course for many living with chronic thromboembolic pulmonary hypertension.