Blood Disorders Pulmonary Embolism Guide Pulmonary Embolism Guide Overview Symptoms Causes Diagnosis Treatment Prevention Causes and Risk Factors of Pulmonary Embolism By Richard N. Fogoros, MD facebook linkedin Richard N. Fogoros, MD, is a retired professor of medicine and board-certified in internal medicine, clinical cardiology, and clinical electrophysiology. Learn about our editorial process Richard N. Fogoros, MD Medically reviewed by Medically reviewed by Sanja Jelic, MD on August 07, 2019 Sanja Jelic, MD is board-certified in pulmonary disease, sleep medicine, critical care medicine, and internal medicine. She is an assistant professor and attending physician at Columbia University College of Physicians and Surgeons in New York, NY. Learn about our Medical Review Board Sanja Jelic, MD Updated on November 02, 2020 Print Table of Contents View All Table of Contents Common Cause Risk Factors Next in Pulmonary Embolism Guide Diagnosing a Pulmonary Embolus A pulmonary embolus is caused when a foreign material lodges in and obstructs (embolizes) the pulmonary artery or one of its branches. Most often, the foreign material is a blood clot, but in rare cases other conditions can be at fault. Pulmonary embolism is a common medical condition. It can underlie serious illness and accounts for an estimated 60,000 to 100,000 deaths per year in the United States. There are several lifestyle risk factors you can control to reduce your chances of pulmonary embolism. © Verywell, 2018 Common Cause Pulmonary embolus typically stems from deep vein thrombosis, which can have a variety of causes. If a thrombus (blood clot) that has formed in a major vein breaks off, travels through the right side of the heart, and lodges in the pulmonary circulation, it becomes a pulmonary embolus. Pulmonary embolus and deep vein thrombosis are so closely tied that if a doctor diagnoses or suspects one of these conditions they immediately will look for evidence that the other condition is also present. Rarer Causes Conditions other than deep vein thrombosis associated with a pulmonary embolus can produce critical illness or death. They include: Fat embolism: A fat embolism can occur if fatty tissue is damaged or manipulated, causing clumps of fat cells to enter the circulation, where they can lodge in the pulmonary circulation. The most common cause of fat embolism is fracture of the pelvis or long bones, whose marrow contains large amounts of fat.Air embolism: If air enters the circulation it can occlude a pulmonary artery or other artery. Air embolism can result from almost any type of surgical procedure, or in divers who ascend too rapidly.Amniotic fluid embolism: Rarely, amniotic fluid can enter the circulatory systme during a difficult childbirth and produce acute pulmonary embolism. Although very rare, aminoitc fluid embolism is life-threatening.Tumor embolism: If cancer cells enter the circulation in large numbers they can occlude pulmonary vessels. This complication of cancer is usually seen only in people with nearly end-stage disease. Risk Factors Because a pulmonary embolus is almost always the result of deep vein thrombosis, the risk factors for these two conditions are virtually identical. 2:22 Common Causes & Risk Factors for Blood Clots These include risk factors related to a person’s lifestyle, including: Not getting enough exercise: Being habitually sedentary promotes venous insufficiency, which predisposes to blood clot formation in the major veins.Being overweight: Carrying too much weight also promotes pooling of blood in the veins of the lower extremities.Smoking: Smoking causes inflammation in the blood vessels, which can lead to excess clotting. In fact, smoking is an especially powerful risk factor for abnormal blood clotting. In addition to these chronic, lifestyle-related risk factors, there are other conditions that can substantially increase a person’s risk of pulmonary embolus. Some of these risks are temporary or situational in nature; others create a more chronic, long-term risk for pulmonary embolus: Recent surgery, hospitalization, or trauma that leads to extended immobilizationLong trips that involve to prolonged sittingTrauma that causes tissue damage that may lead to blood clots.PregnancyMedications, especially birth control pills, hormone replacement therapy, testosterone supplements, tamoxifen, and antidepressantsChronic liver diseaseChronic kidney diseaseSignificant cardiovascular disease, especially heart failureHaving had either deep vein thrombosis or or pulmonary embolus in the past.Certain genetic conditions can make the blood hypercoagulable (prone to clotting) Anyone with any of these conditions should make every effort to reduce the risk factors under their control to lower their risk of developing venous thrombosis and pulmonary embolus. Getting plenty of exercise and keeping weight in control are important; not smoking is critical. Diagnosing a Pulmonary Embolus Was this page helpful? Thanks for your feedback! Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Centers for Disease Control and Prevention. Data and statistics on venous thromboembolism. Updated March 14, 2019. American Thoracic Society. Pulmonary embolism. Updated February 2017. Kosova E, Bergmark B, Piazza G. Fat embolism syndrome. Circulation. 2015 Jan 20;131(3):317-20. doi: 10.1161/CIRCULATIONAHA.114.010835 Gordy S, Rowell S. Vascular air embolism. Int J Crit Illn Inj Sci. 2013;3(1):73-76. doi:10.4103/2229-5151.109428 Thongrong C, Kasemsiri P, Hofmann JP, et al. Amniotic fluid embolism. Int J Crit Illn Inj Sci. 2013;3(1):51-57. doi:10.4103/2229-5151.109422 Latchana N, Daniel VC, Gould RW, Pollock RE. Pulmonary tumor embolism secondary to soft tissue and bone sarcomas: A case report and literature review. World J Surg Oncol. 2017;15(1):168. 2017 Aug 30. doi:10.1186/s12957-017-1223-3 Cleveland Clinic. Pulmonary embolism: Who is at risk. Updated July 15, 2019. Centers for Disease Control and Prevention. What is venous thromboembolism? Updated March 14, 2019. Additional Reading Alotaibi GS, Wu C, Senthilselvan A, McMurtry MS. Secular trends in incidence and mortality of acute venous thromboembolism: The AB-VTE population-based study. Am J Med. 2016 Aug;129(8):879.e19-25. doi:10.1016/j.amjmed.2016.01.041 Søgaard KK, Schmidt M, Pedersen L, et al. 30-year mortality after venous thromboembolism: A population-based cohort study. Circulation. 2014; 130:829. doi:10.1161/CIRCULATIONAHA.114.009107