Blood Clots

  • Medical Author:
    Benjamin Wedro, MD, FACEP, FAAEM

    Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.

  • Medical Editor: Melissa Conrad Stöppler, MD
    Melissa Conrad Stöppler, MD

    Melissa Conrad Stöppler, MD

    Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

Quick GuideDeep Vein Thrombosis (DVT): Symptoms, Treatment & Prevention

Deep Vein Thrombosis (DVT): Symptoms, Treatment & Prevention

What causes blood clots (blood clots in veins or arteries)?

Blood clots form when there is damage to the lining of a blood vessel, either an artery or a vein. The damage may be obvious, such as a cut or laceration, or may not be visible to the naked eye. Blood also will begin to clot if it stops moving, and becomes stagnant, or in diseases that cause the blood to clot abnormally.

Blood clots in a vein (venous thrombosis) occur when a person becomes immobilized and muscles are not contracting to push blood back to the heart. This stagnant blood begins to form small clots along the walls of the vein. This initial clot can gradually grow to partially or completely occlude or block the vein and prevent blood from returning to the heart.

An analogy to this process is a slow moving river. Over time, weeds and algae start to accumulate along the banks of the river where the water flows more slowly. Gradually, as the weeds start to grow, they begin to invade the center of the river because they can withstand the pressure of the oncoming water flow.

Blood clots in an artery (arterial thrombi) occur by a different mechanism. For those with atherosclerotic disease, plaque deposits form along the lining of the artery and grow, which causes the vessel to narrow. This disease process may cause

If a plaque ruptures, a blood clot can form at the site of that rupture and can completely or partially occlude the blood flow at that point. Continue Reading

Reviewed on 4/27/2016
References
REFERENCES:

Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012;141(2_suppl):

Dzsheka MS, et al. Stroke and bleeding risk in atrial fibrillation. Clin Cardiol.2014, Oct, 37(10)

Medscape. Deep Vein Thrombosis and Thrombophlebitis.

Fauci, Anthony S., et al. Harrison's Principles of Internal Medicine. 17th ed. United States: McGraw-Hill Professional, 2011.

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