An aneurysm is a bulge in an artery—a vessel that carries oxygen-rich blood from the heart to the rest of the body—caused by weakened artery walls. Several factors, such as high blood pressure or congenital defects, can increase the risk. While aneurysms most often develop in the aorta—the body’s main artery—they can occur in any artery. When aneurysms occur in brain arteries (a condition called cerebral aneurysm), they can lead to brain hemorrhaging and stroke.

Anyone can develop an aneurysm, but certain types are more common in specific populations. Symptoms vary depending on severity and location. In serious cases, the aneurysm may rupture, leading to internal bleeding, which can be life-threatening. Fortunately, various treatments are available.

Types of Aneurysm

Aneurysms are classified based on the location in the body. Understanding the type helps determine symptoms and possible complications. The four primary types include thoracic aortic, abdominal aortic, cerebral, and peripheral aneurysms.

Thoracic Aortic Aneurysm

This type occurs in the upper part of the aorta (the thoracic region). It involves the artery enlarging by at least 50% of its normal diameter. These aneurysms affect the part of the aorta that passes through the chest.

Abdominal Aortic Aneurysm

Abdominal aortic aneurysms occur in the lower portion of the aorta, supplying blood to the abdomen, pelvis, and legs. These aneurysms swell to about 150% of their typical size due to arterial wall weakness.

Cerebral Aneurysm

Cerebral aneurysms involve the arteries in the brain. The most common form is the saccular aneurysm, where a sac forms on the artery wall, often at branching points near the brain’s base. Fusiform aneurysms, which bulge all around the artery, are another form.

Peripheral Aneurysm

Peripheral aneurysms occur in arteries outside the heart and brain, often in the legs (popliteal aneurysms) or abdomen (splenic aneurysms). Though rare, they can lead to internal bleeding or clots.

Symptoms

Symptoms vary based on the type and severity of the aneurysm.

Thoracic Aortic Aneurysm Symptoms

Most thoracic aortic aneurysms have no symptoms. If complications occur, signs can include:

  • Sudden, sharp pain in the chest or upper back

  • Breathing issues or shortness of breath

  • Trouble swallowing

Abdominal Aortic Aneurysm Symptoms

This type is also often symptom-free, but possible signs include:

  • Deep, throbbing pain in the back or side

  • Pain in the buttocks, groin, or legs

Cerebral Aneurysm Symptoms

Symptoms appear mainly when the aneurysm becomes large or ruptures. Signs of an unruptured aneurysm include:

  • Pain above or behind the eye

  • Numbness or weakness

  • Enlarged pupil in one eye

  • One-sided facial paralysis

  • Vision issues or double vision

If it ruptures:

  • Sudden, severe headache

  • Nausea or vomiting

  • Double vision

  • Stiff neck

  • Sensitivity to light

  • Seizures

  • Loss of consciousness or cardiac arrest

Peripheral Aneurysm Symptoms

Usually symptomless, but may cause:

  • Abdominal pain

  • Fainting

  • Sudden leg pain, weakness, swelling, or numbness

  • Discoloration or pain in toes

What Causes an Aneurysm?

Aneurysms result from thinning or weakening of the artery walls. The causes can be congenital or acquired later in life.

Risk Factors

General risk factors include:

  • Smoking

  • Family history

  • High blood pressure

  • Age over 65

  • Connective tissue disorders (e.g., Marfan or Ehlers-Danlos)

  • Physical trauma

Specific risks:

  • Abdominal aneurysms: male sex, Caucasian ethnicity, high cholesterol, atherosclerosis, cystic medial necrosis, syphilis, HIV

  • Thoracic aneurysms: genetic predisposition, chronic obstructive pulmonary disease (COPD)

  • Cerebral aneurysms: drug use (cocaine/amphetamines), age over 40, polycystic kidney disease, brain trauma, tumors, infections

Diagnosis

Most aneurysms are discovered incidentally during tests for other issues. Diagnostic methods include:

  • Physical examination (palpation)

  • Ultrasound

  • CT scan

  • MRI

  • Magnetic resonance angiography (MRA)

  • Echocardiography

  • Cerebral angiography

  • Cerebrospinal fluid (CSF) analysis

Treatments for Aneurysm

Treatment depends on location and severity. Milder cases are monitored, while others require medication or surgery.

Prescription Medications

These help manage blood pressure and other symptoms:

  • Calcium-channel blockers

  • Angiotensin receptor blockers

  • Anticonvulsants

  • ACE inhibitors

  • Statins

  • Beta-blockers

Surgeries

Surgical options include:

  • Open surgical repair (especially for thoracic or abdominal aneurysms)

  • Endovascular repair (less invasive, using stents)

  • Flow diversion (used in cerebral aneurysms)

  • Shunt placement (to relieve brain pressure)

  • Endovascular therapy (minimally invasive graft placement)

  • Microvascular clipping (blocks blood flow at aneurysm site)

  • Platinum coil embolization (uses coils to reduce blood flow in brain aneurysms)

Rehabilitative Therapies

Brain aneurysms causing hemorrhage may lead to lasting effects. Occupational and physical therapy may help improve cognitive, motor, and speech functions.

Prevention

To reduce aneurysm risk:

  • Get regular screenings

  • Control blood pressure

  • Quit smoking

  • Follow a heart-healthy diet

  • Exercise regularly

  • Avoid recreational drug use

Comorbid Conditions

Aneurysms are associated with several conditions:

  • COPD

  • Coronary artery disease (CAD)

  • Peripheral artery disease (PAD)

  • Stroke (from cerebral aneurysm rupture)

  • Gallstones

  • Diverticulosis

Living With an Aneurysm

Although often asymptomatic, aneurysms can be fatal if ruptured. The good news is that rupture is rare and proper monitoring helps reduce risk. With appropriate management—like controlling blood pressure, staying active, eating well, and avoiding tobacco—people with aneurysms can live long, healthy lives.