The German physician Rudolf Ludwig Virchow (1821–1902) was a pioneer of public health, advocating modern sewage disposal and food safety inspections. But he began his brilliant career researching pathology. In 1847, he noticed a number of clots in the arteries of animals. Virchow theorized that the clots blocked bloodflow to the heart, resulting in heart attacks. Fragments from other, larger blood clots, such as those in leg or arm veins, could break off and travel to smaller, remote vessels, starving tissues of blood and oxygen. “That gives rise to the very frequent process on which I have bestowed the name of Embolia,” he wrote.

alt

Today, experts know that this condition—called an embolism—can occur when clot fragments block blood vessels in the legs, feet, kidneys, intestines, or eyes. A clot close to the skin is generally harmless, but those in veins deep in the body, known as deep vein thrombosis, can be harmful. For instance, an embolism in an artery in the brain can cause a stroke, while one in the heart may lead to a heart attack. Another common form is a pulmonary embolism, in which a vein leading to a lung becomes clogged. Symptoms include shortness of breath, radiating chest pain, a bloody cough, and rapid heartbeat.

People with atherosclerosis (hardening of the arteries) and high blood pressure are at greater odds of experiencing an embolism. Having a sedentary lifestyle or a smoking habit or being overweight or obese increases the risk. Embolisms are treated in a variety of ways, depending on where they’re located. Thrombolytic drugs can dissolve clots, while anticoagulants and antiplatelet medications can prevent new clots from forming. Other cases may require surgery, such as an artery bypass, clot removal, or angioplasty (opening the artery with a catheter).

ADDITIONAL FACTS

  1. Sitting for long periods of time can slow bloodflow, which may lead to the formation of clots in at-risk people.
  2. Embolisms can also be caused by pieces of tissue, cholesterol crystals, clumps of bacteria, or amniotic fluid.