Pulmonary embolism - Causes

What are causes of pulmonary embolism?

Various causes can be considered.  A vessel occlusion caused by thrombosis is the main cause. In nine of ten patients, such a blood clot originates from the arteries of the pelvis or legs.  This thrombus passes through the inferior vena cava through the right heart into the right or left lung artery. If a large vessel is clogged, symptoms occur very fast. These occur mostly in the morning after waking up and defecation or after a sudden effort. The clot is then released by pressure fluctuations and reaches the lungs.

Doctors differentiate two types of risk factors for a thrombosis and therefore also for a pulmonary embolism: the so-called dispositional and expositional risk factors.

  • The dispositional risks include congenital (e.g. inheritable defects of blood clotting) and acquired (e.g. obesity or chronic diseases) factors, which concern the patient.
  • The term “expositional risk” comprises all external influences. Especially surgeries (e.g. knee or hip joint replacement, interventions on the spine), severe injuries of the spine, of the pelvis and legs, as well as longer bed rest or bed confinement are associated with an increased risk.