​Pulmonary Embolism

Pulmonary embolism is a disease in which one of the arteries in your lungs gets blocked. It is usually caused by a blood clot that starts in your leg, thigh or any other part of your body, which then travels to the lungs. In most cases the blood clot is small and can be treated if diagnosed in time, but if it is large enough to stop the flow of blood to the lungs, it can prove to be fatal. A clot that develops close to your skin is not as dangerous, and usually does not cause any problems. However a clot that is lodged in a vein deep within your body can be very dangerous, and is known as Deep Vein Thrombosis (DVT). When DVT occurs in conjunction with pulmonary embolism, the disease is known as venous thromboembolism. 

Several factors lead to higher risk of developing blood clots. These include:

  • Long periods of inactivity, such as bed rest after surgery, during illness or during a long flight

  • Diseases such as cancer, heart failure, stroke or severe infections

  • Birth control pills 

  • Smoking

  • Major surgeries involving the hips, brain or legs

  • Pregnancy or childbirth, especially a caesarean section

  • Hypercoagulable state or blood clotting disorder

Sometimes blockages other than blood clots may also develop. These include tumours, air bubbles or amniotic fluid (that is, the fluid surrounding the baby in the womb). It is also caused by obesity (being overweight) or old age.

The symptoms of pulmonary embolism differ depending on the circumstances, such as size of the blood clot and history of heart and lung disease. The usual symptoms are:​

  • ​Chest pain

  • Coughing

  • Pain and/or swelling in the leg or calf

  • Shortness of breath

  • Sweating

  • Fever

  • Dizziness

  • Irregular heartbeat

  • Skin discoloration​

If you are experiencing chest pain that lasts longer than a few minutes, shortness of breath or blood in your sputum, visit your doctor immediately. The Heart, Lungs and Vascular services at The Aga Khan University Hospital offer quality health care and a range of treatment options. If you need an ambulance, call the Aga Khan University Hospital’s 24/7 Emergency and Acute Care Services immediately.​

Your time with your doctor maybe limited, so make sure to prepare for your visit beforehand. Here ​are some tips to help get you started.​

Pulmonary embolism can sometimes be difficult to diagnose as it often presents with same symptoms as a heart attack, panic attack or pneumonia, so your doctor will first take a medical history to rule these out. An initial physical examination will be conducted to check for abnormalities such as swelling, heartbeat irregularity etc. Then he/she will conduct one or several tests in order to check for blood clots in order to confirm the diagnosis of pulmonary embolism. These include:​

  • ECG/EKG (Electrocardiogram): this procedure is used to test your heartbeat to detect unusual patterns which signal a heart attack.

  • Echocardiogram: this procedure uses sound waves to produce images of the heart which can then be examined to check for muscle damage or other abnormalities

  • Chest X-ray: a detailed image of your heart and lungs is captured by an X-ray machine which the doctor examines in detail to check for irregularities.

  • Blood tests to check for presence of a clot dissolving substance known as D dimer. High levels of this indicate that the likelihood of blood clots is also higher. Blood tests can also determine whether you have a blood clotting disorder.

  • CT (Computerized Tomography) scan: this provides images of your heart and lungs to show if any of the arteries have abnormalities. 

  • Ultrasound: In this procedure, high frequency sound waves are used to check for blood clots in your veins. A device known as a transducer is used to send sound waves to the veins which create a moving image on a computer screen, which can then be checked for presence of clots.​​

It is vital to receive prompt treatment for pulmonary embolism, as it may prove to be fatal if left untreated. One option for treatment is the use of medication such as blood thinners (also known as anticoagulants). This can be injected intravenously or through the skin and it helps to break up the clots as well as prevent new ones from forming. It can also be taken orally, or both treatments can be carried out simultaneously. This type of medication may have some side effects, including bleeding. Another type of medication used to treat pulmonary embolism is clot dissolvers, also known as thrombolytics. It works quickly but the side effects, including bleeding, are very severe so this is only used in life threatening situations. 

Clots can also be removed surgically, using a thin tube known as a catheter. Again, this is a specialized form of treatment and is only used in situations when a clot has been lodged in your lungs and is restricting normal breathing function to a vast extent.  A catheter can also be used to insert a filter into the vein that leads to your heart. This filter prevents clots from travelling to your lungs. This procedure is used when anticoagulant drugs are not effective or cannot be administered due to other reasons.​

The Aga Khan University Hospital offers various support services to help with managing or recovering from the disease or condition. These include but are not limited to nutrition, physiotherapy, rehabilitation, specialized clinics and some patient support groups. Your doctor or nurse will advise you accordingly.

The Aga Khan University Hospital offers financial assistance to those who are in need and fulfil the eligibility criteria. For further information, you can contact the Patient Welfare Department. You can find the contact number of the Patient Welfare Department in the ‘Important Numbers’ section on the website homepage.​

The financial counselling staff is available during office hours, at the main PBSD (Patient Business Services Department), to answer your financial queries on treatments’ costs and authorize admissions on partial deposit as per hospital policies allow. The financial counsellor in the emergency room is open 24/7. You can find the contact number of the Patient Business Services in the ‘Important Numbers’ section on the website homepage.​

Your doctor and or nurse will give you specific instructions about the prescribed medication. Please ensure that you take or use the prescribed medicine as advised. It can be dangerous to your health if you self-prescribe. Please inform the doctor or nurse beforehand if you have experienced any adverse reactions to any medications in the past. If you experience any symptoms of drug poisoning, overdose or severe reaction please contact the Pharmacy Service at The Aga Khan University Hospital immediately. You can find the contact number of the Pharmacy Services in the ‘Important Numbers’ section on the website homepage.​




The information provided on our website is for educational purposes and not intended to be a substitute for medical advice, diagnosis or treatment. You should always seek the advice of your doctor or other healthcare professional provider.