Chronic Mesenteric Ischemia - Types, Causes, Symptoms, and Treatment

What Is Mesenteric Ischemia?

Mesenteric ischemia is a medical condition that causes decreased blood supply to the small intestine due to blocked or narrow blood vessels. This decreased blood flow or blood supply to the small intestine can cause permanent and serious damage to the small intestine. Mesenteric ischemia is a symptom of peripheral vascular disorder in which the blood flow is insufficient to meet the requirements of the visceral organs to function efficiently. The condition is classified into two subtypes depending upon the time of onset of the disease.

What Are the Types of Mesenteric Ischemia?

The types of mesenteric ischemia are:

• Acute Mesenteric Ischemia: Acute mesenteric ischemia occurs due to a sudden decrease in the blood supply to the small intestine. Common symptoms of acute mesenteric ischemia include; sudden and severe pain in the abdomen, fever, nausea, and vomiting.

• Chronic Mesenteric Ischemia: Chronic mesenteric ischemia occurs due to a reduction in the blood flow to the small intestine over a long period of time. Common symptoms of chronic mesenteric ischemia include; pain in the abdomen after half an hour of eating something, pain that worsens over time, and then subsides after three to four hours.

What Is Chronic Mesenteric Ischemia?

Chronic mesenteric ischemia is a type of mesenteric ischemia that develops over a long period. The condition is characterized by decreased blood flow to the small intestine that fails to meet the requirement of the visceral organs. This reduced blood flow to the small intestine causes the inability of the organ to metabolize and function properly. Acute mesenteric ischemia causes excruciating pain and may require immediate surgical intervention; however, chronic mesenteric ischemia causes vague symptoms that may be misdiagnosed as other common abdominal problems.

What Causes Chronic Mesenteric Ischemia?

A reduction in blood flow to the small intestine is the primary cause of acute and chronic mesenteric ischemia. A blood clot in the main mesenteric artery is the most frequent cause of acute mesenteric ischemia, and these blood clots frequently start in the heart. The most frequent cause of chronic mesenteric ischemia is an accumulation of plaque that constricts the arteries.

Moreover, there are several risk factors that can cause chronic mesenteric ischemia:

• Diabetes.

• Hypertension (increased blood pressure).

• Smoking.

• Increased levels of lipids, cholesterol, and triglycerides in the blood (hyperlipidemia).

• Old age.

• Heart diseases like coronary heart disease, atrial fibrillation, and heart failure.

• Pancreatitis and other inflammatory conditions.

• Cocaine abuse.

What Is the Prevalence Rate of Chronic Mesenteric Ischemia?

• Chronic mesenteric ischemia is a rare condition, and it accounts for only one in about every 1000 hospital admission for abdominal pain.

• However, stenosis associated with mesenteric ischemia is fairly common and affects approximately ten percent of people who are above 65 years of age.

• The average patient has symptoms of other co-existing atherosclerotic diseases and is between the ages of 50 and 70.

• Women are more commonly affected by chronic mesenteric ischemia as compared to men.

What Are the Symptoms of Chronic Mesenteric Ischemia?

The signs and symptoms of chronic mesenteric ischemia include:

• Abdominal ischemia or pain in the abdomen.

• Post-prandial pain in the abdomen (pain in the abdomen within 15 minutes and half an hour of eating).

• Abdominal pain that lasts for up to four hours.

• Patients may develop a fear of eating because of the pain.

• Weight loss.

• Nausea and vomiting.

• Diarrhea.

• Constipation.

• Feeling full early while eating.

• The majority of individuals will have a history of angina, transient ischemia episodes, and other signs of diffuse atherosclerotic disease.

• The majority of the time, a physical exam will demonstrate no rebound or guarding and only diffusely moderate stomach discomfort.

How Is Chronic Mesenteric Ischemia Diagnosed?

Diagnosis of chronic mesenteric ischemia is often delayed by the comprehensive gastrointestinal diseases workup that most patients have for common reasons of abdominal pain and weight loss, like peptic ulcers, cholecystitis, and cancer. Therefore, chronic mesenteric ischemia can be diagnosed in the following ways:

• CT (Computed Tomography) Angiography: The standard first-line, non-invasive technique for the diagnosis of chronic mesenteric ischemia is CT (computed tomography) angiography since it detects or excludes mesenteric vascular atherosclerotic stenosis while also excluding other abdominal causes.

• Arterial Digital Subtracted Angiography: If the results of non-invasive imaging are ambiguous, arterial digital subtracted angiography is the gold standard for verifying the diagnosis of chronic mesenteric ischemia and is used to design treatment modalities.

• Doppler Ultrasound: With this non-invasive test, blood flow is estimated using sound waves, which can reveal artery narrowing.

• Blood Examinations: Tests that count white blood cells and evaluate the blood's acidity could be useful in making a diagnosis.

How Is Chronic Mesenteric Ischemia Treated?

• With the help of antiplatelet medication and smoking cessation, asymptomatic patients with chronic mesenteric ischemia are treated conservatively. The mortality rate for these individuals at five years is 40 percent, with the majority of fatalities occurring due to cardiovascular or myocardial infarction.

• Patients with untreated symptomatic chronic mesenteric ischemia have a five-year death rate close to 100 percent; therefore, it requires either open or endovascular revascularization therapy.

• Surgery is indicated in the case of; the presence of peritonitis, gastrointestinal hemorrhage, persistent abdominal pain and fever, symptoms persistent for up to 21 days, chronic malabsorption, and ischemic stricture (a band of scar tissue caused by chronic ischemia).

What Are the Possible Complications of Chronic Mesenteric Ischemia?

Some of the common complications of chronic mesenteric ischemia are:

• Malnutrition.

• Infections.

• Ischemia of the colon due to thrombosis (blood clots blocking blood vessels).

• Bleeding in the gastrointestinal tract.

• Prolonged ileus (a painful obstruction of the ileum or other parts of the gut).

Conclusion:

Chronic mesenteric ischemia is an uncommon condition affecting the small intestine and occurring due to reduced blood flow to the visceral organs. The primary symptom of the condition is post-prandial abdominal pain. The majority of chronic mesenteric ischemia patients have a poor quality of life. Significant weight loss results from the ongoing worry that ingesting food would cause abdominal pain. Other metabolic and endocrine issues, bone weakening, and susceptibility to bruising are frequently caused by malnutrition associated with chronic mesenteric ischemia.