Pulmonary Embolism

Pulmonary embolism is a serious condition that most often occurs when a blood clot formed in the veins of the leg or pelvis breaks loose and blocks one of the pulmonary arteries. It is commonly described as “a clot going to the lung.” Depending on the size of the blockage and the person’s overall condition, the picture may range from mild shortness of breath to sudden circulatory collapse. For this reason, newly developed unexplained shortness of breath and pleuritic chest pain should be taken seriously. ^[1][2][3]

Pulmonary embolism is part of the broader group known as venous thromboembolism and is closely linked to deep vein thrombosis. Just as not every leg pain means a clot, not every pulmonary embolism begins with dramatic symptoms. Sometimes the findings may be subtle; however, if not treated promptly, the condition may become life-threatening. Risk should be assessed especially carefully in people who have recently had surgery, remained immobile for a long time, have cancer, or have a history of blood clots. ^[1][2][3]

What are the symptoms of pulmonary embolism?

The most common symptoms are sudden shortness of breath, sharp chest pain or pain that worsens with breathing, palpitations, and an unexplained sense of distress. Some people may also develop cough, bloody sputum, fainting, dizziness, or excessive sweating. As the clot burden increases, blood pressure may fall, the heart may come under strain, and the emergency can become more severe. However, small emboli may sometimes present only with exertional shortness of breath or mild chest discomfort. ^[1][2][3]

Unilateral leg swelling, pain, warmth, or tenderness may be associated with deep vein thrombosis and increase the risk of pulmonary embolism. However, a clot may still travel to the lungs even in the absence of these symptoms. Shortness of breath developing in people who use oral contraceptives or hormone therapy, during pregnancy or the postpartum period, in the presence of active cancer, or after prolonged bed rest should be evaluated more carefully. ^[1][2]

What causes it, and what are the risk factors?

The most common cause of pulmonary embolism is migration of clots formed in the deep veins to the lungs. Immobility, long-distance travel, major surgery, trauma, fractures, cancer, advanced age, inherited clotting disorders, pregnancy, and some hormonal medications may increase the risk. A prior history of blood clots is also an important risk marker. However, embolism may occur even in people without known risk factors, so it is not safe to wait simply because “I have no risk factors.” ^[1][2][3]

Three main factors facilitate clot formation: slowed blood flow in the vessel, damage to the vessel wall, and increased tendency of the blood to clot. Although these mechanistic details are not always discussed in routine clinical practice, they explain why symptoms beginning after prolonged immobility matter. For this reason, early mobilization after surgery, preventive blood thinners in appropriate patients, and compression methods are used. ^[1][3]

How is it diagnosed?

Pulmonary embolism is not diagnosed solely on the basis of symptoms. The doctor first evaluates the level of risk and the clinical probability. In some patients, the D-dimer test may help rule out the possibility of a clot, but it does not establish a definite diagnosis on its own. CT pulmonary angiography is one of the most commonly used imaging methods in current practice. In some situations, ventilation-perfusion scintigraphy, lower-extremity ultrasound, ECG, chest X-ray, and echocardiography also contribute to the evaluation. ^[1][2][3]

Speed matters in diagnosis, because if treatment is delayed, the right side of the heart may come under strain and the circulation may deteriorate. However, acting quickly does not mean starting random treatment. Especially in people with bleeding risk, treatment must be chosen carefully. For this reason, in someone with chest pain and shortness of breath, emergency evaluation is safer than starting aspirin or any other medication on one’s own. ^[1][2]

How is it treated?

The main goals of treatment are to prevent the existing clot from growing, prevent new clots from forming, and reduce the life-threatening circulatory burden. For this reason, blood thinners are the cornerstone of treatment in many patients. Which medication is used and for how long depends on the severity of the embolism, the underlying cause, bleeding risk, and the person’s coexisting medical conditions. Some patients require hospitalization, whereas selected low-risk patients may be followed as outpatients under close supervision. ^[1][2][3]

In severe cases, clot-dissolving medications, catheter-based procedures, or surgery may be considered. A more aggressive approach may be necessary, especially in people with low blood pressure, shock, severe oxygen impairment, or right heart strain. After treatment, assessment of recurrence risk, movement planning, travel precautions, and long-term preventive therapy in some patients are important. ^[1][2][3]

When is emergency help needed?

Emergency evaluation is required if there is sudden shortness of breath, chest pain, fainting, bloody sputum, unexplained rapid heartbeat, or marked one-sided swelling in the leg. These signs may indicate pulmonary embolism and belong to the group of conditions in which minutes can matter. The risk should be taken even more seriously when there is a recent history of surgery, long travel, childbirth, cancer treatment, or immobility. ^[1][2]

A person with suspected pulmonary embolism should not attempt to diagnose themselves and wait at home. This content is intended for general information; individual risk, diagnosis, and treatment require specialist evaluation. Early diagnosis and appropriate anticoagulant treatment can prevent serious complications in many patients. However, details such as bleeding risk, kidney function, and the underlying cause must always be assessed by a physician. ^[1][2][3]

Prevention and reducing the risk of recurrence

Assessing the risk of recurrence is an important part of treatment in a person who has had pulmonary embolism. Planning preventive measures during periods of prolonged immobility, preoperative risk assessment, preventive medications in appropriate individuals, and early mobilization may all help reduce the likelihood of recurrence. However, which preventive approach is suitable depends on the individual’s bleeding risk and history of clotting. ^[1][3]

FAQ

Are pulmonary embolism and deep vein thrombosis the same thing?
No, they are not the same, but they are closely related. Deep vein thrombosis refers to a clot in the veins of the leg or pelvis, whereas pulmonary embolism refers to that clot traveling to the lungs. ^[1][3]

Can pulmonary embolism be fatal?
Yes. Large clots and cases that impair circulation can be life-threatening. ^[1][2]

Can it occur without symptoms?
Some small emboli may cause milder symptoms, but there are usually signs such as shortness of breath, chest pain, or palpitations. ^[1][2]

How long does treatment last?
Treatment duration varies from person to person. The cause of the clot, recurrence risk, and bleeding risk all affect this decision. ^[2][3]

Can the risk of clotting during travel be reduced?
In appropriate individuals, movement breaks, adequate fluid intake, and preventive measures recommended by a physician may help reduce the risk. ^[1][3]