Last reviewed by Dr. Raj MD on January 12th, 2022.
Pseudoaneurysm is also referred to as false aneurysm and is described as a dilated artery that resulted from a leak in the artery. In pseudoaneurysm, the hematoma is formed outside the arterial wall and the surrounding tissue.
Pseudoaneurysm can be distinguished from a true aneurysm where in pseudoaneurysm the communication of blood flow between the aneurysm lumen and the vessel lumen is still continuing. Pseudoaneurysm can occur in any part of the body and generally resolves on its own although there are cases where treatment is required to prevent complication and hemorrhage and to control the leakage.
A true aneurysm is defined as a localized dilatation of the artery and characterized by a swelling of the blood vessel. The size of the swelling can be quite small or can be very large and the swelling can continue to increase in size as the pressure continues to buildup thereby increasing the risk for rupture that can lead to a severe hemorrhage and a serious medical complication or may even lead to death of the patient. True aneurysm is not caused by a puncture in the blood vessel but is rather due to the weakness in the arterial wall or may be due to other underlying conditions that caused damage to the arterial wall.
The difference between pseudoaneurysm and a true aneurysm can be distinguished through the manner of blood leakage. The blood leakage in pseudoaneurysm is outside the arterial wall and into the surrounding tissues while in true aneurysm the leakage is confined within the arterial wall.
Pseudoaneurysm can occur in any arterial segment of the body and can even occur in the cardiac chamber with femoral artery pseudoaneurysm as the most common. Pseudoaneurysm can involve different locations such as:
- Femoral artery
- Carotid artery
- Peripheral artery
- Visceral artery
- Brachiocephalic artery
The different locations that can be involved in pseudoaneurysm can have various signs and symptoms although the disease is generally presented with a pulsatile mass that is tender and painful. The skin over the affected area may also be erythematous or may be reddish that is often mistaken with an abscess. The swelling in pseudoaneurysm can be quite small but it increases in size that the pulsatile mass in the affected area can be observed as gradually increasing in size.
The incidence of pseudoaneurysm is usually asymptomatic in most patients. The formation of pseudoaneurysm may take some time such as several days to several months or may even take several years following a penetrating or blunt injury that caused the leaking hole in the artery.
The most common cause of pseudoaneurysm is a blunt or penetrating injury that can puncture the artery resulting in a leaking hole.
Penetrating trauma, such as from gunshot wounds, stabbing wound and any form of trauma or injury that can cause a piercing wound is potential for pseudoaneurysm. The penetrating wound causing hole in the arterial wall will allow the blood to leak through the adjacent tissue forming the pseudoaneurysm.
A blunt trauma such as a kick in the shin or an ankle sprain can also result to pseudoaneurysm when the arterial wall is damaged enough to cause a leaking hole.
Laceration and puncture from procedures such as arterial catheterization, biopsy and endovascular procedure are potentials for pseudoaneurysm to develop. Endovascular procedure for example requires introduction of thins wires and special instrument that have to pass through the femoral artery. Pseudoaneurysm is also to be a complication of cardiac catheterization where the blood leak is caused by the puncture made by the catheter inserted.
Other causes of pseudoaneurysm include the following:
- Mycotic aneurysm
- Myocardial infarction
- Chronic pancreatitis
- Acute pancreatitis
- Penetrating atherosclerotic ulcer
- Takayasu arteritis
- Giant cell arteritis
Pseudoaneurysm usually resolves on its own without treatment. There are cases where treatment is necessary particularly if the size has grown big enough to lead to a rupture and cause a serious medical complication that can be life-threatening.
Surgery used to be the standard treatment for pseudoaneurysm although less invasive methods are now being performed. Pseudoaneurysm on the other hand necessitates a careful diagnosis or should be properly and accurately diagnosed prior to treatment. Imaging tests such as ultrasound, MR angiography and CT angiography can be utilized to properly determine pseudoaneurysm including its extent and location.
Treatment of pseudoaneurysm includes the following:
Surgery or surgical repair is indicated for a badly damaged artery that is causing blood leakage or if blood flow to distant tissues and muscle is badly disrupted. This method of treatment is necessary if reconstruction of damaged artery is warranted and to restore a normal blood flow.
Ultrasound probe compression
This is a less invasive method where the ultrasound probe is pressed on the skin of the patient to compress the narrow path of pseudoaneurysm to introduce clotting. This method however is not a flourishing choice among obese patients and those taking aspirin for quite some time.
Ultrasound guided thrombin injection
This is also a minimally invasive method that utilizes an ultrasound probe to guide the thrombin injection through the pseudoaneurysm. The aim of the treatment is to introduce a thrombin into the pseudoaneurysm to stimulate clotting.
Covered stent is a less invasive method of treating pseudoaneurysm and is regarded to have a high success rate. The aim of the covered stent is to prevent the blood leakage by covering the hole of the artery.