What is an embolus?

An embolus is accurately defined as a foreign object that is circulating in the bloodstream. This can include a variety of substances, such as blood clots (thrombi), air bubbles, fat globules, or even fragments from a tumor. When an embolus travels through the bloodstream, it can obstruct a blood vessel, potentially leading to serious health complications depending on where the blockage occurs, such as in the lungs (pulmonary embolism) or the brain (stroke).

The other options presented refer to related but different concepts. A blood clot specifically causing heart attacks points to a thrombus rather than an embolus, while high blood pressure is classified medically as hypertension, not associated with the definition of an embolus. Lastly, a medication used to break down clots, such as thrombolytics, is a therapeutic approach for treating existing thrombi but does not define what an embolus is.