Aneurysm treatment ranges from regular monitoring with no intervention at all to emergency surgery, depending on the aneurysm’s size, location, and whether it has ruptured. Most small, unruptured aneurysms are managed with blood pressure control and periodic imaging. Larger or symptomatic aneurysms typically require a procedure to either seal off the weakened blood vessel from the inside or repair it through open surgery.
When Treatment Is Needed vs. When Monitoring Is Enough
Not every aneurysm requires surgery. For brain aneurysms, the risk of rupture climbs steeply with size. A large Japanese study tracking thousands of patients found the annual rupture rate was 0.36% for aneurysms 3 to 4 mm wide, but jumped to 1.69% for those 7 to 9 mm, 4.37% for 10 to 24 mm, and a striking 33.4% for aneurysms 25 mm or larger. Aneurysms larger than about 5 mm carry roughly double the rupture risk of smaller ones, and 7 mm is a key threshold where risk rises more sharply. Being female, smoking, and having a family history of aneurysms all push the risk higher.
For abdominal aortic aneurysms, international guidelines recommend considering repair once the diameter exceeds 55 mm in men or 50 mm in women. Below those thresholds, the risks of surgery generally outweigh the risk of rupture.
If your aneurysm falls below the intervention threshold, you’ll enter a surveillance program. The frequency of imaging is tailored to how large the aneurysm is, how fast it’s growing, and how close it is to the surgical cutoff. People with connective tissue conditions like Marfan syndrome or Loeys-Dietz syndrome, or those with a family history of aneurysms, are typically scanned annually. Others with very small, stable aneurysms may be imaged less often. Your doctors will also treat risk factors aggressively during this period, particularly high blood pressure and smoking.
Blood Pressure Control and Lifestyle Changes
Keeping blood pressure in check is the single most important thing you can do to slow aneurysm growth and reduce the chance of rupture. Sudden surges in blood pressure are a recognized trigger for rapid aneurysm growth and rupture. For people with an unruptured aneurysm, the goal is steady, long-term blood pressure management rather than a specific emergency target.
Quitting smoking matters enormously. Smoking is one of the strongest independent risk factors for both aneurysm formation and rupture. Beyond that, the standard advice applies: regular physical activity (within any restrictions your doctor sets), maintaining a healthy weight, and limiting alcohol. These aren’t just general wellness tips. They directly affect the pressure and stress on a weakened artery wall.
Procedures for Brain Aneurysms
Two main approaches exist for repairing a brain aneurysm: surgical clipping and endovascular coiling. The choice between them depends on the aneurysm’s size, shape, location, and your overall health.
Surgical Clipping
A neurosurgeon opens part of the skull and places a small metal clip at the base of the aneurysm, cutting off blood flow to the bulging section. It’s an invasive procedure with a recovery period of at least four to six weeks. The major advantage is durability. Clipped aneurysms have a lower chance of coming back, which means fewer follow-up imaging appointments over the years.
Endovascular Coiling
Instead of opening the skull, a doctor threads a thin catheter through an artery (usually starting in the groin) up to the aneurysm and fills it with tiny platinum coils. These coils cause the blood inside the aneurysm to clot, effectively sealing it off. Recovery is dramatically faster, often around one week. The tradeoff is a higher chance the aneurysm returns over time, so you’ll need routine imaging to check for regrowth.
Flow Diverters
For complex or wide-necked aneurysms that are difficult to treat with coiling, a newer option uses a mesh stent placed across the neck of the aneurysm. This device redirects blood flow away from the aneurysm, causing it to gradually clot and shrink. Flow diverters were originally developed for large and giant aneurysms but are now used for smaller and more difficult-to-reach ones as well.
Procedures for Aortic Aneurysms
Aortic aneurysms, whether in the abdomen or chest, also have two primary repair options: endovascular repair and open surgery.
Endovascular Repair
A stent graft (a fabric-covered tube) is threaded through an artery in the leg and positioned inside the aneurysm. The graft seals against the healthy vessel wall above and below the weakened section, routing blood through the graft and relieving pressure on the aneurysm wall. This is less invasive and involves a shorter hospital stay, but it only works when the anatomy is right. The healthy section of aorta above the aneurysm (called the “neck”) needs to be long enough, the right diameter, and free of heavy calcium buildup or blood clot for the graft to seal properly. If the aneurysm extends too close to the arteries supplying the kidneys or intestines, a standard stent graft won’t work.
Open Surgical Repair
When anatomy rules out the endovascular option, or for complex aneurysms that extend near vital branch arteries, open surgery is the alternative. The surgeon directly accesses the aorta, clamps it above and below the aneurysm, and replaces the damaged section with a synthetic graft. Hospital stays for open aortic repair typically range from three to ten days, and you’ll be restricted from lifting more than ten pounds for four to six weeks afterward, sometimes longer depending on healing.
Emergency Treatment for a Ruptured Aneurysm
A ruptured aneurysm is a life-threatening emergency. Treatment priorities shift to stabilizing the patient and stopping the bleeding as quickly as possible. The same repair techniques (clipping, coiling, or stent grafting) are used, but under emergency conditions with much higher risk.
For ruptured brain aneurysms, blood pressure becomes a critical balancing act. Guidelines recommend keeping systolic blood pressure below 160 mm Hg to reduce further bleeding, while maintaining enough pressure to keep blood flowing to the brain. After the aneurysm is secured, a major concern is vasospasm, where blood vessels in the brain narrow dangerously in the days following the bleed. Patients receive medication to reduce the risk of this complication and the brain damage it can cause. If the rupture causes a buildup of cerebrospinal fluid (putting pressure on the brain), a drainage catheter may be placed to relieve that pressure.
Who Should Be Screened
About 20% of people with a family history of aortic aneurysms or dissections carry a single-gene variant that significantly raises their risk. Screening is particularly important for people diagnosed with aneurysms at a young age, those with rapidly growing or multiple aneurysms, people with connective tissue syndromes like Marfan or Loeys-Dietz syndrome, and anyone with close relatives who have had aneurysms or aortic dissections. For brain aneurysms, AHA guidelines suggest that people with a family history may benefit from treatment even when aneurysms are smaller than the usual size thresholds.
Genetic testing can identify some of these high-risk individuals before an aneurysm ever forms, allowing early surveillance that catches problems when they’re still manageable.
What Recovery Looks Like
Recovery varies widely based on the type of procedure and whether the aneurysm ruptured. For minimally invasive brain procedures like coiling, most people are back to normal activities within a week or two. Surgical clipping requires at least four to six weeks of recovery. Open aortic surgery means a hospital stay of three to ten days, followed by weeks of activity restrictions, no heavy lifting being the most important one.
After any aneurysm repair, long-term follow-up is part of the deal. Endovascular repairs (both brain and aortic) require periodic imaging to confirm the repair is holding and the aneurysm hasn’t returned. The schedule depends on the type of repair and your individual risk factors, but expect at least annual imaging for the first few years. Blood pressure management and lifestyle modifications remain important indefinitely, since having one aneurysm means you’re at higher risk of developing another.