Conditions & Treatments

Thrombosis

Thrombosis occurs when clots obstruct veins (blood vessels that carry blood from the body back into the heart) or arteries (blood vessels that carry oxygenated blood away from the heart to the body).

Thrombosis

What is thrombosis?

Thrombosis occurs when clots obstruct or block veins (blood vessels that carry blood from the body back into the heart) or arteries (blood vessels that carry oxygenated blood away from the heart to the body). Venous thrombosis is when the blood clot obstructs a vein, and arterial thrombosis is when the blood clot obstructs an artery.

What causes thrombosis?

Venous thrombosis may be the result of the following:

  • Disease or injury to the veins in the legs

  • Immobility for any reason

  • Fracture

  • Certain medications

  • Obesity

  • Inherited disorders or inherited predisposition

  • Autoimmune disorders that predispose to clotting

  • Medications, such as certain contraceptives, that increase the risk of clotting 

Pooling (stasis) of blood in the legs and subsequent clotting can result in varicose veins. Clots in the legs may break loose and travel to the lungs, causing pulmonary clots that can result in respiratory distress, pain, and in extreme cases, death.

Arterial thrombosis may be the result of arteriosclerosis, which involves hardening of the arteries where fatty or calcium deposits cause the arterial walls to thicken. This can lead to plaque instability and risk for rupture followed by thrombus.

When arterial thrombosis occurs in the coronary arteries (arteries that branch from the aorta to provide blood to the heart muscle), it can lead to heart attacks. When arterial thrombosis occurs in the cerebral (brain) circulation, it can lead to strokes or lack of oxygen to other organs.

Risk factors for arterial thrombosis may include:

  • Smoking

  • Diabetes

  • High blood pressure

  • High cholesterol

  • Lack of activity and obesity

  • Poor diet

  • Family history of arterial thrombosis 

What are the symptoms of thrombosis?

The following are the most common symptoms of thrombosis. However, each individual may experience symptoms differently. Symptoms may include:

  • Pain isolated to one leg (usually the calf or inner thigh)

  • Swelling in the extremity

  • Chest pain

  • Numbness or weakness on one side of the body

  • Acute mental status changes 

The symptoms of thrombosis may resemble other blood disorders or medical problems. Always consult your doctor for a diagnosis.

How is thrombosis diagnosed?

In addition to a complete medical history and physical examination, diagnostic procedures for thrombosis may include venous and arterial ultrasounds and blood tests including hypercoagulability panels. Dye injection with angiography and catheterization may also be used, as well as MRI/MRA and CT. The diagnostic procedure advised depends on the type of thrombus--venous or arterial--and the location. 

Treatment for thrombosis

Specific treatment for thrombosis will be determined by your doctor based on:

  • Your age, overall health, and medical history

  • Extent and type of thrombosis

  • Your tolerance for specific medications, procedures, or therapies

  • Expectations for the course of the disease

  • Your opinion or preference

Treatment may include:

  • Anticoagulant medications, such as coumadin and heparin

  • Catheters (to expand the width, or lumen, of involved vessels)

  • Stent placement

  • Medications, such as antiplatelets, tissue plasminogen activator (t-PA), and/or enzymes, such as streptokinase (to dissolve clots)

Other treatments may be advised in your particular situation and will be reviewed in detail with you by your doctor.  

Treatment Programs


Massachusetts General Hospital understands that a variety of factors influence patients' health care decisions. That's just one reason why we're dedicated to ensuring patients understand their diagnosis and treatment options. Because a single option might not serve all patients, we offer a wide range of coordinated treatments and related services across the hospital. Patients should consult with their primary care doctor or other qualified health care provider for medical advice and diagnosis information.

Select a treatment program for more information:



Cancer Center

  • Hematology
    The Center for Hematology offers comprehensive diagnosis, treatment, and referral for all blood disorders, ranging from simple anemia to clotting disorders to major hematological cancers.
Imaging

  • Vascular Imaging and Intervention
    Working as part of the Vascular Center, the interventional vascular specialists of the Vascular Imaging and Intervention Program at Massachusetts General Hospital Imaging perform minimally invasive, image-guided treatments for conditions including stroke and peripheral vascular disease. These same interventionalists also use minimally invasive techniques to treat non-vascular conditions including uterine fibroids and certain kinds of cancer. In addition, our specialty-trained radiologists use the latest imaging technologies to provide diagnostic exams for a full range of vascular conditions.
  • Pediatric Imaging
    The Pediatric Imaging Program at Massachusetts General Hospital Imaging specializes in ensuring the safety and comfort of child patients while providing the latest technology and the expertise of specialized pediatric radiologists.
MassGeneral Hospital for Children

  • Hemophilia and Thrombosis Center
    The Hemophilia and Thrombosis Center at MassGeneral Hospital for Children offers comprehensive evaluations and individualized care to children and adults with bleeding disorders due to hemophilia A, hemophilia B, rare clotting factor deficiencies and von Willebrand disease.
Vascular Center

  • Venous Disease Program
    Physicians at the Venous Disease Program at the Massachusetts General Hospital Vascular Center use novel endovenous minimally invasive and endovascular surgical interventions, as well as lifestyle modification strategies to diagnose and treat patients with deep vein thrombosis (DVT), varicose veins and other venous disorders.
Department of Neurology

  • Cardio-Neurology Clinic
    The Massachusetts General Hospital Cardio-Neurology Clinic provides comprehensive neurological evaluation and care for patients with cerebrovascular disorders related to the heart, including patent foramen ovale (PFO).

The following related clinical trials and research studies are currently seeking participants at Massachusetts General Hospital. Search for clinical trials and studies in another area of interest.

Innovative care at the Vascular Center

Learn more about the latest treatment options for this condition at the Vascular Center