How is pulmonary embolism treated? Cardiology Basics

How is pulmonary embolism treated? Cardiology Basics

Pulmonary embolism is obstruction of pulmonary arteries due to emboli migrating from other parts of the body. It is a potentially life threatening condition if a major branch or multiple branches are obstructed. More emboli can travel to the lungs from the original source and hence pulmonary embolism may worsen later even if the initial episode involves only a small portion of the lungs. So, it is important to treat pulmonary embolism even if it is mild. Treatment options will depend on the severity of the situation.

Initial treatment will be with parenteral anticoagulants like heparin or low molecular weight heparin. After stabilization, long term treatment is with oral anticoagulants. Fondaparinux is another parenteral medication which can be used in the initial treatment of pulmonary embolism. As these medications increase the risk of bleeding, close medical supervision is needed. Dose of heparin may be adjusted according to activated partial thromboplastin levels, to maintain therapeutic levels.

Oral anticoagulants belong to two important groups. The time old one is warfarin, which is a vitamin K antagonist. Newer medications are known as non-vitamin K antagonists or NOACs in short. They are also known as direct oral anticoagulants or DOACs. Dabigatran, rivaroxaban and apixaban are important medications belonging to this group.

Warfarin needs regular monitoring of coagulation function with  PT-INR or prothrombin time with international normalized ratio estimation. Usual therapeutic range for INR is 2-3. Dose of warfarin is titrated in small increments or decrements to maintain INR in therapeutic range. NOACs being newer drugs, are costlier but do not need PT-INR monitoring. Bleeding risk is there for both groups of medications and need close medical supervision.

Those with more severe forms of pulmonary embolism with hypotension and right ventricular dysfunction may need thrombolytic therapy. These have even more risk of causing bleeding elsewhere and are usually given only in the intensive care setting with close medical supervision. They cannot be given for those who have bleeding or coagulation disorders.

Another option in case of life threatening situations not responding to medical treatment is surgery to remove the thrombi from the pulmonary arteries. Sometimes special catheters may be used to fragment and aspirate the thrombi from the pulmonary arteries. In patients with recurrent pulmonary embolism, and a contraindication for anticoagulation, an inferior vena caval filter may be deployed. There are retrievable inferior vena caval filters for temporary use as well.

In case of pulmonary embolism, prevention is equally important, both for first episode and for recurrent episodes. One way of prevention is by giving anticoagulants in those at high risk after a surgery or immobilization. Mechanical measures like graded compression stockings and intermittent pneumatic compression devices are also often used in hospitals. A simple way is to move the lower limbs actively or passively as much as possible in situations where the venous return is likely to be sluggish.