Blood clots

Definition

Blood clots are clumps that occur when blood hardens from a liquid to a solid.

A thrombus or embolus can partly or completely block the flow of blood in a blood vessel.

Causes

Situations in which a blood clot is more likely to form in veins include:

Blood clots are also more likely to form after an injury. People with cancer, obesity, and liver or kidney disease are also prone to blood clots.

Smoking also increases the risk of forming blood clots.

Conditions that are passed down through families (inherited) may make you more likely to form abnormal blood clots. Inherited conditions that affect clotting are:

Other rare conditions, such as protein C, protein S, and antithrombin III deficiencies.

A blood clot may block an artery or vein in the heart, affecting the:


Review Date: 5/14/2018
Reviewed By: Preeti Sudheendra, MD, oncologist at the MD Anderson Cancer Center at Cooper, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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