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Overview
Veins carry blood back to the heart from the tissues. Blood flowing in the veins is under lower pressure and moves more slowly than blood flowing in the arteries. Blood is therefore more likely to clot in the veins, thus blocking the flow through the veins.
Review Date 1/25/2022
Updated by: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. 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.