The Bleeding Stopped. Why a Ruptured Brain Aneurysm Is Still an Emergency
Why treatment is still urgent after the bleeding stops
A ruptured brain aneurysm can stop bleeding on its own, but the aneurysm has not repaired itself. Until it is secured, another hemorrhage remains possible.
Dr. Shailesh Male, MD
Board-certified neurologist and neurointerventionalist. NeuroClarified explains complex neurological conditions and treatments in clear, clinically grounded language.
BRAIN ANEURYSM · TREATMENT
A brain aneurysm can rupture, bleed into the space around the brain, and then stop bleeding on its own. That does not mean the danger has passed. The aneurysm can bleed again, which is why doctors work to seal it as early as possible.
What is a brain aneurysm?
Arteries in the brain branch again and again. At a branch point, part of the artery wall can bulge outward into a pouch. That pouch is an aneurysm.
Two parts matter when doctors plan treatment:
- The neck is where the aneurysm joins the artery.
- The dome is the rounded part of the aneurysm.
The shape, size, location, and width of the neck can all affect how an aneurysm is treated.
What happens when an aneurysm ruptures?
When a weak point in an aneurysm tears open, blood escapes under arterial pressure into the fluid-filled space surrounding the brain.
This is called a subarachnoid hemorrhage. It is a type of stroke caused by bleeding rather than by a blocked artery.
As pressure around the brain rises and clotting begins, the initial bleeding may stop. But the aneurysm itself has not been repaired.
Why isn't the danger over when the bleeding stops?
The initial seal can be unstable.
The torn aneurysm remains exposed to the pulsing pressure inside the artery. If that seal fails, the aneurysm can bleed again. Rebleeding carries a high risk of severe disability or death.
For that reason, current guidelines recommend treating the ruptured aneurysm as early as feasible, preferably within 24 hours.
The goal is not to remove the blood that has already escaped. The immediate goal is to prevent another hemorrhage.
Two ways to seal a ruptured aneurysm
The two main treatments are:
- Clipping: a neurosurgeon closes the aneurysm from outside the artery.
- Coiling: an interventional specialist closes the aneurysm from inside the blood vessel.
Both are designed to separate the aneurysm from the circulation while keeping the normal artery open.
Coiling: treating the aneurysm from inside the artery
During coiling, a thin tube called a catheter is inserted into an artery, usually at the wrist or groin. It is guided through the blood vessels toward the brain while the physician watches its position using X-ray imaging.
No opening in the skull is required.
A much smaller catheter is then advanced into the aneurysm. Through it, the physician places very soft platinum coils inside the aneurysm.
The coils slow the movement of blood inside the pouch and provide a framework for clot to form. The goal is to seal the aneurysm off from the circulation while preserving blood flow through the parent artery.
What if the aneurysm has a wide neck?
Some aneurysms have a wide opening where they join the artery. In these aneurysms, coils may not stay securely inside the pouch without additional support.
One option is balloon-assisted coiling. A small balloon is temporarily inflated across the aneurysm neck while the coils are placed. The balloon is then deflated and removed.
Some aneurysms require a stent, a mesh tube that remains in the artery and supports the coils.
Stents require antiplatelet medicines to reduce the risk of clot forming inside the device. Because those medicines affect blood clotting, doctors generally try to avoid a stent during the acute phase after a rupture when the aneurysm can be safely treated another way.
Clipping: treating the aneurysm from outside
Clipping is an operation performed by a cerebrovascular neurosurgeon.
The surgeon creates an opening in the skull, reaches the aneurysm from outside the blood vessel, and places a small metal clip across its neck.
The clip prevents blood from entering the aneurysm while allowing blood to continue flowing through the normal artery.
Is coiling or clipping better?
There is no single answer for every aneurysm.
The choice depends on factors including:
- the aneurysm's location
- its shape and neck width
- the patient's age
- the patient's neurological and medical condition
- the anatomy of the surrounding arteries
The decision is often made jointly by cerebrovascular neurosurgeons and endovascular specialists.
In patients with ruptured aneurysms that were considered suitable for either treatment, the International Subarachnoid Aneurysm Trial found better functional outcomes at one year with endovascular coiling.
That does not mean coiling is always preferable.
Coiled aneurysms are more likely than clipped aneurysms to recur or require additional treatment, which is one reason follow-up imaging is important.
What happens after the aneurysm is sealed?
Securing the aneurysm sharply reduces the danger of another hemorrhage.
But it does not undo the original bleed.
Blood already present around the brain can lead to other complications, including fluid build-up and delayed problems with blood flow to the brain. Patients therefore remain closely monitored after the aneurysm has been treated.
Frequently asked questions
If the bleeding has stopped, why is a ruptured aneurysm still an emergency?
The initial bleeding may stop when clotting temporarily seals the tear. But that seal can fail. Until the aneurysm itself is secured, another hemorrhage remains possible.
Is coiling or clipping better?
Neither treatment is best for every aneurysm. The choice depends on the aneurysm's anatomy and the patient's condition. For aneurysms suitable for either approach, coiling has shown an advantage in functional outcome in selected patients, while clipping generally has a lower risk of aneurysm recurrence.
Can a coiled aneurysm reopen?
Yes. Some coiled aneurysms can partially reopen over time or require another treatment. Follow-up imaging is therefore important.
Why are stents often avoided immediately after an aneurysm rupture?
Stents usually require antiplatelet medicines to reduce clotting inside the device. Immediately after a brain hemorrhage, doctors generally avoid using a stent when the aneurysm can be safely treated without one.
Is the danger over once the aneurysm has been sealed?
The risk of another hemorrhage from the treated aneurysm is greatly reduced, but complications from the original subarachnoid hemorrhage can still develop. That is why monitoring continues after treatment.
Sources and references
- Hoh BL, et al. 2023 Guideline for the Management of Patients With Aneurysmal Subarachnoid Hemorrhage: A Guideline From the American Heart Association/American Stroke Association. Stroke. 2023;54:e314–e370. doi:10.1161/STR.0000000000000436.
- Molyneux A, et al. International Subarachnoid Aneurysm Trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomised trial. Lancet. 2002;360:1267–1274. doi:10.1016/S0140-6736(02)11314-6.
- Molyneux AJ, et al. International Subarachnoid Aneurysm Trial (ISAT): a randomised comparison of effects on survival, dependency, seizures, rebleeding, subgroups, and aneurysm occlusion. Lancet. 2005;366:809–817. doi:10.1016/S0140-6736(05)67214-5.
- Raymond J, et al. Long-term angiographic recurrences after selective endovascular treatment of aneurysms with detachable coils. Stroke. 2003;34:1398–1403. doi:10.1161/01.STR.0000073841.88563.E9.