What is deep vein thrombosis (DVT)?

Deep vein thrombosis (DVT) is a blood clot (thrombus) in a deep vein, usually in the legs. These clots require medical care right away.

These clots are dangerous because they can break loose, travel through the bloodstream to the lungs, and block blood flow in the lungs (pulmonary embolism). Pulmonary embolism is often life-threatening. DVT can also lead to long-lasting problems. It may damage the vein and cause the leg to ache, swell, and change color.

Clots can also form in superficial veins. Blood clots with inflammation in superficial veins (called superficial thrombophlebitis or phlebitis) rarely cause serious problems.

Blood clots most often form in the calf and thigh veins, and less often in the arm veins or pelvic veins. Diagnosis and treatment of DVT in other parts of the body are similar.

Condition Spotlight

Clearing Pathways: Imaging and Reimagining Open New DVT Treatment Doors Watch Video
Your Health: Ronald Dalman, MD, Discusses Venous Disease
Your Health: Ronald Dalman, MD, Discusses Venous Disease Play Video | 3:10
Removing Tiny Filter Embedded in Vein Takes Expertise Unique to Stanford Hospital
Removing Tiny Filter Embedded in Vein Takes Expertise Unique to Stanford Hospital Play Video | 3:38

Clinical Trials for Deep Vein Thrombosis (DVT)

Clinical trials are research studies that evaluate a new medical approach, device, drug, or other treatment. As a Stanford Health Care patient, you may have access to the latest, advanced clinical trials.

Open trials refer to studies currently accepting participants. Closed trials are not currently enrolling, but may open in the future.

Open Trials Closed Trials

Clinics for Deep Vein Thrombosis (DVT)