Aneurysms

An aneurysm is a weakening of an artery wall that causes a bulge or balloon-like expansion. Aneurysms can occur in any artery — most seriously in the aorta (the largest artery in the body) or the arteries of the brain. They are dangerous because they can rupture, causing catastrophic internal bleeding. Most aneurysms cause no symptoms until they grow large or rupture.

Common types

• Abdominal aortic aneurysm (AAA) — in the abdomen; often silent; more common in men, smokers, older adults
• Thoracic aortic aneurysm — in the chest
• Brain aneurysm — covered in a separate page
• Peripheral artery aneurysm — in leg or knee arteries
• Visceral artery aneurysm — in arteries supplying the abdominal organs

Risk factors

• High blood pressure — the biggest modifiable risk factor
• Smoking — particularly for AAA
• Atherosclerosis (hardening of arteries)
• Age — more common after 60
• Male sex (for aortic aneurysms)
• Family history
• Inherited connective-tissue disorders — Marfan syndrome, Ehlers-Danlos, vascular EDS
• Infections (mycotic aneurysm — rare)
• Trauma
• Syphilis (historically, in untreated cases)

Symptoms

Most aneurysms have no symptoms. Large ones may cause:

• A pulsating mass (e.g. in the abdomen for AAA)
• Back or abdominal pain
• Chest or back pain (thoracic)
• Hoarseness or swallowing difficulty (pressing on nearby structures)
• Signs of reduced blood flow downstream

Ruptured aneurysm — medical emergency. Dial 112.

• Sudden severe pain (abdomen, back, chest — depending on site)
• Rapid heart rate, low blood pressure, pale clammy skin
• Collapse
• Untreated aortic rupture is rapidly fatal

Diagnosis

Often found incidentally on a scan done for another reason. Screening is offered for some groups — in some countries, men over 65 are offered a one-off AAA ultrasound. Your doctor can advise if you're at higher risk.

Treatment

Depends on size, location, growth rate, and symptoms:

• Small aneurysms — often monitored with regular ultrasounds, with blood-pressure control and lifestyle changes
• Larger or rapidly-growing aneurysms, or those causing symptoms — repair before they rupture
• Endovascular repair — a stent-graft placed through a catheter; less invasive
• Open surgical repair — for some cases
• Emergency repair — for rupture — urgent vascular surgery; mortality high but unavoidable without it
• Strict blood-pressure control, not smoking, and treating atherosclerosis risk factors across the board