A blood clot, or thrombus, is a collection of blood cells that forms inside a blood vessel, impeding blood flow. Rarely, a blood clot may form in the abdomen. Doctors refer to this as mesenteric venous thrombosis (MVT).

An MVT is so-called because it involves a thrombus in the superior mesenteric vein (SMV) in the abdomen. This vein drains blood from the small intestine and parts of the large intestine.

A blockage here can cause symptoms, but not always. Possible symptoms include abdominal pain and swelling, nausea, and vomiting.

This article outlines the causes of a blood clot in the abdomen and lists the symptoms and risk factors.

It also provides information on diagnosing and treating a blood clot in the abdomen and considers the outlook for people who have a blood clot or have had one in the past.

What is a blood clot in the stomach?

A woman lying on an examination table getting her stomach examined for a clot.

A deep vein thrombosis (DVT) is a blood clot that occurs in one of the deep veins of the body.

DVTs most commonly occur in the deep veins of the legs. They can also develop in deep veins within the abdomen or pelvis.

Medical professionals use the term “mesenteric venous thrombosis (MVT)” to refer to a blood clot in the superior mesenteric vein (SMV) in the abdomen.

The SMV is a major vein that drains blood from the small intestine and parts of the large intestine.

In MVT, a blood clot forms inside the SMV, impairing the vein’s ability to drain blood from the intestines.

What are the symptoms of a blood clot in the stomach?

Blood clots can form in the deep veins of the legs, abdomen, or pelvis. Although the location of the blood clot may differ, the symptoms can be similar.

They may include:

  • pain and swelling in the area
  • warm, red, or darkened skin around the painful area
  • swollen veins that are hard or sore to the touch

Acute vs. chronic MVT symptoms

MVT can be sudden (acute) or ongoing (chronic).

The most common symptom of acute MVT is severe pain in the mid-abdomen. Other possible symptoms include:

  • abdominal pain and tenderness
  • abdominal bloating
  • nausea
  • vomiting

People with chronic MVT often do not present with any symptoms. They may instead learn about their condition while undergoing tests for a separate health issue.

Is an abdominal blood clot a sign of cancer?

According to Cancer Research UK, people with cancer have an increased risk of developing blood clots. Cancers of the following organs are associated with a particularly increased risk of blood clots:

  • stomach
  • pancreas
  • kidney
  • bladder
  • uterus
  • lung
  • brain

Although there is a link between cancer and blood clots, having a blood clot does not necessarily mean a person has cancer.

Many factors can increase a person’s risk of developing blood clots, and cancer is not the most common.

What are the risk factors for developing a blood clot in the stomach?

According to the American Society of Hematology, various factors can affect a person’s risk of developing blood clots, including:

  • how quickly the body reacts to signals that tell it when and where to form a clot
  • the speed with which blood flows through the veins
  • the speed with which the blood clots

The American Society of Hematology lists the following as factors that can increase a person’s risk of developing blood clots:

  • smoking
  • pregnancy
  • being immobile or inactive for prolonged periods
  • having overweight or obesity
  • being over age 60 years
  • having a family history of blood clots
  • taking oral contraceptives (birth control pills)
  • having high blood pressure
  • having high cholesterol
  • having certain health conditions, such as:
    • diabetes
    • chronic inflammatory diseases
    • certain types of cancer
  • sustaining an injury

How do doctors diagnose a blood clot in the stomach?

When diagnosing a blood clot in the abdomen, a doctor begins by asking about a person’s symptoms and medical history as well as their family history. If the doctor suspects MVT, they will refer the person for abdominal imaging.

According to research, X-rays reveal MVT-related abnormalities in around 50–75% of cases but only show evidence of intestinal ischemia in less than 5% of cases.

A CT scan with contrast is preferable, detecting 90% of MVTs, and demonstrating a superior ability to detect intestinal ischemia.

How do doctors treat a blood clot in the stomach?

According to the American Society of Hematology, the treatment for a blood clot depends on its location and the person’s overall health.

Some potential treatment options for blood clots are outlined below.

Medications

Doctors may administer medications called thrombolytics to help dissolve existing blood clots. An example is tissue plasminogen activator (tPA).

Doctors may also prescribe medications called anticoagulants to help prevent additional blood clots from forming. Examples include:

  • injectable anticoagulants, such as heparin, or low molecular weight heparin
  • oral anticoagulants, such as:
    • apixaban
    • dabigatran
    • edoxaban
    • rivaroxaban
    • warfarin

Surgery

In some cases, a doctor may perform catheter-directed thrombolysis. This procedure involves inserting a long tube called a catheter into a vein and directing it toward the blood clot. The surgeon then uses the catheter to deliver a clot-dissolving medication directly into the clot.

Alternatively, a doctor may perform a thrombectomy. This procedure involves inserting a device through a catheter to help pull or suck out a blood clot.

What is the outlook for a person with a blood clot in their stomach?

Around one- to two-thirds of people with acute MVT develop an intestinal infarction. This is a blockage within one or more of the arteries supplying the small intestine.

Intestinal infarction can lead to a potentially life threatening condition called intestinal ischemia. It is characterized by a 75% or more reduction in intestinal blood flow over more than 12 hours.

Intestinal ischemia has a high rate of death. It requires emergency medical treatment in a hospital setting.

Undergoing treatment for MVT reduces the risk of complications, including intestinal infarction and intestinal ischemia.

The National Blood Clot Alliance acknowledges that recovery from a blood clot can be challenging and overwhelming. However, after successful treatment, most people fully recover and can resume their normal activities.

Summary

A blood clot is a collection of blood cells that forms inside a blood vessel, impeding blood flow. Most blood clots form in the deep veins within the legs, though they occasionally form in the abdomen.

A mesenteric venous thrombosis (MVT) is a blood clot that forms in the superior mesenteric vein (SMV) in the abdomen. This vein drains blood from the small intestine and parts of the large intestine. As such, a blockage here can cause gastrointestinal symptoms, such as abdominal pain and swelling, nausea, and vomiting.

Anyone who suspects they may have a blood clot should seek immediate medical attention. Without urgent treatment, a blood clot can lead to potentially life threatening complications.

People with an increased risk of developing blood clots can talk with their doctor about ways to reduce their risk.