Visceral Artery Aneurysms - Causes, Symptoms, Diagnosis, and Management

Introduction:

Visceral artery aneurysms are weak spots in the walls of the arteries in the stomach. Due to the pressure in the blood vessels, these weak spots swell out. They could be harmful if they rupture and release blood inside the body. Symptoms are not common in most persons. On imaging tests that they order for other diseases, providers frequently discover them by accident.

What Are Visceral Arteries?

Blood vessels known as visceral arteries arise from the aorta, the body's major artery. Blood is delivered to the abdominal organs through visceral arteries, including:

• Intestines.

• Kidneys.

• Liver.

• Pancreas.

• Spleen.

• Stomach.

Most frequently, visceral artery aneurysms develop in the arteries that provide blood to the liver, kidneys, and spleen.

What Kinds of Aneurysms Occur in the Visceral Arteries?

The two types are true aneurysms and pseudoaneurysms (false aneurysms):

• Pseudoaneurysms: They happen when the arterial wall develops a hole and blood collects in the artery tissue. The blood clotting process creates a fragile wall around the blood pool. Pseudoaneurysms have a higher chance of rupturing because this wall can be fragile.

• True Aneurysms: They occur when a portion of a weakened arterial wall expands.

How Frequent Are Aneurysmal Visceral Arteries?

Aneurysms in the visceral arteries are unusual. However, how frequently they happen is still determined because many people do not experience the symptoms. In addition, some visceral artery aneurysms occur more frequently in women than men. For instance, females are more prone to have aneurysms in the artery leading to their spleen than men.

What Are the Distribution of Visceral Artery Aneurysms?

The following describes the distribution of visceral artery aneurysms:

• Aneurysm of the splenic artery (60%).

• Aneurysm in the hepatic artery (20 to 50%).

• Aneurysm of the superior mesenteric artery (6%).

• Celiac artery aneurysm (4%).

• False aneurysm (rare).

• Mycotic aneurysm (rare).

The splenic artery aneurysm is the most frequent, followed by the hepatic artery and the superior and inferior mesenteric arteries.

What Are the Causes of Visceral Artery Aneurysms?

True aneurysms are typically caused by the following:

• Atherosclerosis.

• Connective tissue conditions like Marfan syndrome, Ehlers-Danlos syndrome, and fibromuscular dysplasia.

• Trauma caused by an accident or injury.

Pseudoaneurysms typically happen because of the following:

• Surgery-related harm to the pancreas or liver.

• Pancreatitis.

• The trauma brought on by an incident or an injury.

• Vasculitis.

What Are the Symptoms of Visceral Artery Aneurysms?

People typically do not exhibit symptoms. However, providers frequently discover visceral artery aneurysms during medical imaging exams for other diseases. Since the level of discomfort can vary from minor to severe, the disorder is occasionally difficult to identify. The primary symptoms of a ruptured visceral artery aneurysm are:

• Anemia.

• Pain in the back or abdomen.

Other signs and symptoms can include:

• Vomiting blood.

• Passing blood in stool, depending on where the aneurysm is located.

• Gastrointestinal bleeding.

• Jaundice.

• Cholestasis.

• Impaired intestinal passage.

What Are the Chances of Visceral Artery Aneurysm in Pregnancy?

Young pregnant mothers and multiparous women have the highest incidence of visceral artery aneurysms. For the expectant mother and the unborn child, a spontaneous rupture of a visceral artery aneurysm is a dangerous and potentially fatal pregnancy condition. The death rate for women is between 70 and 75 percent, while it is between 90 and 95 percent for unborn children.

What Are the Chances of Visceral Artery Rupture During Pregnancy?

Numerous ideas propose primarily hemodynamic and hormonal alterations in the final stages of pregnancy as the pathomechanisms of aneurysm formation during pregnancy. Surprisingly, it has been observed that pregnancy causes up to 40% of splenic artery aneurysms and nearly 100% of superior mesenteric artery aneurysms to rupture. Particularly dangerous times include the latter trimester and the first several days after delivery. Between 24 and 45 percent of visceral artery aneurysms burst during this time; nevertheless, case reports have also mentioned first-trimester pregnancy rupture. Therefore, most of which are coincidental observations on ultrasonography, the indications to treat all visceral artery aneurysms discovered during pregnancy should be broadly established.

How Is Visceral Artery Aneurysm Diagnosed?

Providers use medical imaging procedures like CT scans and MRIs to diagnose visceral artery aneurysms. These examinations measure the aneurysm's size, which is crucial for determining the best course of treatment.

• Angiography - Minimally invasive test; if other imaging tests reveal a problem, it might assist the doctor in evaluating the blood vessels. The doctor places a tiny tube called a catheter into one of the veins during an angiography. A contrast dye is injected after the catheter is threaded into the damaged visceral artery.

• X-Ray or CT (Computed Tomography) Scan - The contrast in the artery is picked up by X-rays or CT scans, which reveal any abnormalities.

• Doppler Duplex Ultrasonography - Visceral artery aneurysms are shown as spherical, hypoechoic, and perfused masses, depending on the size of the thrombus' rim.

When Should a Visceral Artery Aneurysm Be Treated?

Treatment is the best course of action for any aneurysm that can rupture. This comprises:

• False aneurysms of any size.

• True aneurysms that measure more than 2 millimeters (except splenic artery aneurysms, which healthcare professionals advise treating when larger than 3 millimeters).

If an aneurysm is more likely to rupture, the person might still require therapy. The risk could be increased if the person:

• Is either expecting or child-bearing.

• Has persistent symptoms such as back or stomach pain or anemia.

• Needs to undergo a liver transplant or another operation to treat cirrhosis.

Regardless of size, some visceral artery aneurysms must be treated immediately. This is due to the increased chance of them rupturing. These comprise aneurysms in:

• The Gastroduodenal Artery - The pancreas, the tip of the small intestine, and the stomach are all supplied with blood by the gastroduodenal artery.

• Pancreaticoduodenal Artery - Carries blood to the pancreas and the first part of the small intestine.

• The Superior Mesenteric Artery - Supplies blood to the small intestine.

What Kinds of Treatments Are Available for Visceral Artery Aneurysms?

Open surgery and minimally invasive endovascular techniques are the two main therapeutic options. The factors determining the therapies are:

• Blood vessels' structure, including their dimensions.

• The aneurysm's location.

• Age and general health-related risk factors for open surgery.

1. Open Surgery - A wide incision is necessary to provide the surgeon immediate access to the aneurysm during open surgery. The injured portion of the artery is cut out and replaced or repaired by the surgeon.

2. Minimally Invasive Endovascular Technique - A catheter is placed into an artery, typically in the groin, to access the aneurysm during minimally invasive therapy. One or more methods, such as the following, may be applied through the catheter to offer support and prevent a rupture:

   • Coil or Plug Embolization - Packing the aneurysm with a wire coil or mechanical plug.

   • Liquid Embolization - Injection of glue, gel, or similar liquid substance.

   • Stenting - Inserting a metal mesh tube coated with fabric inside the artery.

Conclusion:

Although it is thought that visceral artery aneurysms are uncommon, the advancement of imaging techniques has increased our ability to detect them. The first diagnostic used to identify splanchnic aneurysms and track asymptomatic lesions is ultrasound. In addition, asymptomatic and burst visceral artery aneurysms can be treated successfully with endovascular techniques.