Review of Pulmonary Embolism

About this course

Pulmonary embolism is the third most common cardiovascular disease after coronary artery disease and stroke. It is a serious and deadly form of venous thromboembolic disease, for which an individual’s risk increases with age and multiple inherited and acquired factors. This independent learning activity provides an overview of pulmonary embolism, its risk factors, and treatment options.

Learning objectives

• Define pulmonary embolism.
• Differentiate the various types of pulmonary embolism.
• Review risks factors for pulmonary embolism.
• Review treatment options for pulmonary embolism.
• Understand contraindications for thrombolysis.

Course outline

18 sections · finish in any order across devices

1. 1

   Introduction

   The circulatory system, also called the cardiovascular system, consists of arteries, veins, capillaries, and the heart. The circulatory system’s function is to move blood throughout the body. The cycle begins when the right atrium receives deoxygenated blood from the inferior vena cava and superior

   4 min

2. 2

   What is Pulmonary Embolism?

   A blood clot that forms elsewhere in the body and then breaks off and travels to the blood vessels in the lungs and lodges there, restricting blood flow and interrupting gas exchange, resulting in a life-threatening disease, is called a pulmonary embolism.1,2,3 Blood clots can develop in both veins

   4 min

3. 3

   Acute Pulmonary Embolism

   Acute pulmonary embolism is a common health concern with a variable clinical presentation that makes diagnosis challenging.5 Acute pulmonary embolism occurs when there is a disruption in blood flow in the lungs due to an embolus, initially formed elsewhere in the body, breaking off and lodging into

   4 min

4. 4

   Symptoms

   Following are some of the common symptoms associated with acute pulmonary embolism:5,7

   4 min

5. 5

   Subacute Pulmonary Embolism

   Subacute massive pulmonary embolism is characterized by symptom onset of 2 to 12 weeks, without a solid episode of cardiovascular collapse and pulmonary angiogram showing massive pulmonary embolus (>50% obstruction in major pulmonary arteries).9 It has a high mortality rate and occurs insidiously fo

   4 min

6. 6

   Chronic Pulmonary Embolism

   Chronic thromboembolic pulmonary hypertension (CTEPH) is a long-term complication of acute PE.10,11 In most PE cases, patients are fully recovered once treated, with the emboli resolved and the blood flow restored, but in some cases, residual clots remain attached to pulmonary vessels walls, which l

   4 min

7. 7

   Symptoms

   Chronic pulmonary embolism symptoms are nonspecific and related to the development and progression of pulmonary hypertension.11 The following are some of the common symptoms associated with CTEPH:10,11

   4 min

8. 8

   Causes and Risk Factors

   The most common cause of PE is deep venous thrombosis (DVT). There are over 10 million cases per year of DVT, associated with high rates of morbidity and mortality.4 While the true incidence of PE is unknown, in the United States, it is estimated that nearly a third of hospitalized patients are at r

   4 min

9. 9

   Diagnosis and Treatment

   Diagnosis of pulmonary embolism is difficult as its symptoms are similar to those of multiple other diseases and conditions.1 Thus, the first step to providing optimal treatment involves risk stratification.14 Risk stratification of pulmonary embolism patients is based on hemodynamic consequences, i

   4 min

10. 10

    Respiratory Support

    Supportive interventions are the initial treatment options for PE patients.5 For instance:5,15

    4 min

11. 11

    Anticoagulation

    For acute PE, anticoagulation is a mainstay for treatment.5 For this purpose, both low-molecular-weight heparin (LMWH), fondaparinux, or unfractionated heparin (UFH) can be used for anticoagulation.5 They have their pros and cons; for instance, LMWH has a smaller risk of major bleeding or heparin-in

    4 min

12. 12

    Hemodynamic Support

    Patients that show clinical evidence of hypoperfusion, such as diminished urine output or changes in mental state, require hemodynamic support.15 It also depends on the patient’s baseline blood pressure; generally, intravenous fluids (IVF) of normal saline in small volumes are administered.15 Intrav

    4 min

13. 13

    Hemodynamically Stable

    Hemodynamically stable patients are heterogenous and include low-risk, intermediate-low-risk, and intermediate-high-risk PE patients.15 Treatment is also determined based on the risk of bleeding, for instance:15

    4 min

14. 14

    Anticoagulation

    Anticoagulation therapy is further divided into initial, long-term, and indefinite based on the patient’s needs.15 For instance, initial anticoagulation therapy is administered as soon as possible to achieve therapeutic anticoagulation quickly.15 Whereas, after discharge, a patient continues a minim

    4 min

15. 15

    Inferior Vena Cava Filter

    An inferior vena cava filter is used to block the emboli’s path and prevent it from entering the pulmonary circulation.5 A vena cava filter is considered for the following patients:5,15

    4 min

16. 16

    Thrombolysis

    Thrombolysis, also known as thrombolytic therapy, is a widely accepted treatment for hemodynamically unstable PE patients.5,15 It reduces pulmonary artery pressure and resistance as compared to unfractionated heparin alone.5 It is recommended for patients with a symptom onset of 48 hours or whose sy

    4 min

17. 17

    Catheter-Directed Therapies

    Multiple catheter-directed therapies are available that involve the insertion of a catheter into pulmonary arteries.5,15 The following table describes the modalities:

    4 min

18. 18

    Conclusion

    To conclude, PE patients are treated based on their risk profile and hemodynamic status.16 For instance, hemodynamically unstable PE patients at high risk are considered for thrombolysis.16 If thrombolysis is contraindicated or fails, catheter-directed modalities or surgical embolectomy are consider

    4 min

This course satisfies

Requirement summaries come from our state requirement records. Always confirm details with your board before you renew.

References and resources

• Johns Hopkins Medicine. Pulmonary Embolism. Johns Hopkins Medicine. Published 2019. https://www.hopkinsmedicine.org/health/conditions-and-diseases/pulmonary-embolism
• American Thoracic Society. https://www.thoracic.org/patients/patient-resources/resources/pulmonary-embolism.pdf
• Clark AC, Xue J, Sharma A. Pulmonary Embolism: Epidemiology, Patient Presentation, Diagnosis, and Treatment. Journal of Radiology Nursing. 2019;38(2):112-118. doi:https://doi.org/10.1016/j.jradnu.2019.01.006
• Turetz M, Sideris A, Friedman O, Tripathi N, Horowitz J. Epidemiology, Pathophysiology, and Natural History of Pulmonary Embolism. Seminars in Interventional Radiology. 2018;35(02):92-98. doi:https://doi.org/10.1055/s-0038-1642036
• Vrinda Vyas, Amandeep Goyal. Acute Pulmonary Embolism. Nih.gov. Published August 10, 2020. https://www.ncbi.nlm.nih.gov/books/NBK560551/
• Martinez Licha CR, McCurdy CM, Maldonado SM, Lee LS. Current Management of Acute Pulmonary Embolism. Annals of Thoracic and Cardiovascular Surgery. 2020;26(2):65-71. doi:https://doi.org/10.5761/atcs.ra.19-00158
• Morrone D, Morrone V. Acute Pulmonary Embolism: Focus on the Clinical Picture. Korean Circulation Journal. 2018;48(5):365. doi:https://doi.org/10.4070/kcj.2017.0314
• Rali PM, Criner GJ. Submassive Pulmonary Embolism. American Journal of Respiratory and Critical Care Medicine. 2018;198(5):588-598. doi:https://doi.org/10.1164/rccm.201711-2302ci
• Solanki NN, Tanwar N, Solanki ND. Subacute Massive Pulmonary Embolism Treated With Streptokinase. Cureus. Published online October 25, 2020. doi:https://doi.org/10.7759/cureus.11157
• Klok FA, Couturaud F, Delcroix M, Humbert M. Diagnosis of chronic thromboembolic pulmonary hypertension after acute pulmonary embolism. European Respiratory Journal. 2020;55(6):2000189. doi:https://doi.org/10.1183/13993003.00189-2020
• Nishiyama KH, Saboo SS, Tanabe Y, Jasinowodolinski D, Landay MJ, Kay FU. Chronic pulmonary embolism: diagnosis. Cardiovascular Diagnosis and Therapy. 2018;8(3):253-271. doi:https://doi.org/10.21037/cdt.2018.01.09
• CDC. What is Venous Thromboembolism? | CDC. Centers for Disease Control and Prevention. Published February 10, 2020. https://www.cdc.gov/ncbddd/dvt/facts.html#:~:text=Deep%20vein%20thrombosis%20(DVT)%20is
• Deep Vein Thrombosis (DVT) / Thrombophlebitis. www.hopkinsmedicine.org. https://www.hopkinsmedicine.org/health/conditions-and-diseases/deep-vein-thrombosis-dvt-thrombophlebitis
• Dudzinski DM, Giri J, Rosenfield K. Interventional Treatment of Pulmonary Embolism. Circulation: Cardiovascular Interventions. 2017;10(2). doi:https://doi.org/10.1161/circinterventions.116.004345
• UpToDate. www.uptodate.com. Accessed August 27, 2022. https://www.uptodate.com/contents/treatment-prognosis-and-follow-up-of-acute-pulmonary-embolism-in-adults#H117884119
• Erythropoulou-Kaltsidou A, Alkagiet S, Tziomalos K. New guidelines for the diagnosis and management of pulmonary embolism: Key changes. World Journal of Cardiology. 2020;12(5):161-166. doi:https://doi.org/10.4330/wjc.v12.i5.161

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