Pulmonary embolism: when a clot reaches the lungs
A medical emergency that can look deceptively mild
Dr. Elise Fabre
Pulmonologist
In simple terms
Recognising the symptoms, understanding the tests, and knowing what treatment and follow-up involve.
What it is, in plain words
A pulmonary embolism happens when a clot, almost always from a leg or pelvic vein, travels through the heart and blocks an artery in the lungs. Part of the lung still receives air but no blood, so oxygen cannot be picked up and the right side of the heart suddenly has to work against a blocked circuit.
Signs to look out for
- Sudden breathlessness, at rest or on minimal effort
- Sharp chest pain that gets worse when you breathe in
- Rapid heart rate and rapid breathing
- Coughing, sometimes with blood
- Fainting, sweating, and low blood pressure in massive embolism
Why it happens
The risk factors are the same as for deep vein thrombosis: recent surgery or immobilisation, cancer, pregnancy and the postnatal period, hormonal contraception, long travel, obesity, smoking, and inherited clotting tendencies.
How doctors confirm it
Assessment uses a probability score, a D-dimer test, and CT pulmonary angiography, which shows the clot directly. A ventilation-perfusion scan is used when contrast or radiation must be avoided. An echocardiogram and troponin assess strain on the right heart and guide how aggressive treatment should be.
Treatments and solutions
- Immediate anticoagulation, often before imaging is complete when suspicion is high
- Direct oral anticoagulants for most patients, for at least three months
- Thrombolysis, medicine that dissolves the clot, for patients with shock or severe right heart strain
- Catheter or surgical clot removal when thrombolysis is contraindicated
- A vena cava filter only when anticoagulation is truly impossible
Living with it day to day
Follow-up matters: breathlessness that persists after three to six months should be assessed for chronic thromboembolic pulmonary hypertension, which is treatable. Ask whether your anticoagulant should continue long term, and about screening the family if you are young with no trigger.
When to seek medical help
This is always an emergency. Call for help immediately rather than waiting to see if breathing improves.
This article explains general health information in simple language. It does not replace advice from your own doctor.
The words explained
Medical terms used above, in everyday language.
- Chronic
- A problem that lasts a long time, usually more than three months, and often comes back.
- Risk factor
- Something that makes an illness more likely, such as smoking or family history.
- Hormone
- A chemical messenger made by your body that tells organs what to do.
- Blood pressure
- The force of blood pushing against your artery walls. Too high, over years, damages the heart and vessels.
- Screening
- A check-up done before you feel ill, to catch a problem early.
When should you see a doctor?
- Your symptoms last more than a few weeks or keep coming back.
- They get worse quickly, or stop you doing everyday things.
- You notice sudden pain, breathing trouble, fainting or bleeding — seek urgent care.
- You already take medication and want to change anything about it.
This article explains general health information. It does not replace advice from your own doctor.
Frequently asked questions
- What is Pulmonary embolism: when a clot reaches the lungs?
- Recognising the symptoms, understanding the tests, and knowing what treatment and follow-up involve.
- What are the main symptoms or signs of Pulmonary embolism: when a clot reaches the lungs?
- Common signs vary from person to person. The article above lists the symptoms to watch for, how they progress, and when they need medical attention.
- When should you see a doctor for Pulmonary embolism: when a clot reaches the lungs?
- See a doctor if symptoms last more than a few weeks, get worse quickly, stop you doing everyday things, or if you notice sudden pain, breathing trouble, fainting or bleeding.
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