Arteriovenous Malformations Follow-up

Updated: Dec 04, 2016
  • Author: Souvik Sen, MD, MPH, MS, FAHA; Chief Editor: Helmi L Lutsep, MD  more...
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Further Outpatient Care

Seizure and/or headache medications usually are managed by the neurologist or referring physician.

Follow-up neuropsychological assessments may be helpful if subtle cognitive impairments are noted.

Patients who have suffered hemorrhage may need inpatient or outpatient rehabilitation like other patients with stroke.


Further Inpatient Care

The algorithm for surgical treatment is highly individual and is based on the angiographic characteristics of the AVM.

The most common treatment scenario is one or more endovascular embolization sessions during separate hospitalizations, followed by surgical resection or radiosurgery.

When hemorrhages occur as the presenting event, a longer hospitalization may be required, with supportive care during recovery from the brain hemorrhage.



The most dreaded complication of an AVM's natural history is intracerebral hemorrhage (see Prognosis). Treatment decisions are based on the natural history-risk of first or subsequent hemorrhage versus the risk-benefit ratio of treatment.

Surgical complications

Surgical complications may include persistent neurological deficits associated with hemorrhage and stroke.

Surgical outcome risk correlates with score on the Spetzler-Martin scale; higher scores, seen with large-sized AVMs, deep venous drainage, and location of the AVM in eloquent brain regions, increase the surgical risk.

A recent meta-analysis reports a morbidity of 8.6% and mortality of 3.3% after mostly surgical treatment in a series of 2452 patients. [17] The surgical risk for morbidity and mortality for Spetzler-Martin grade of less or equal to 3 has been reported to be 2-6.3% and 0-2%, respectively. The surgical risk for morbidity and mortality for Spetzler-Martin grade IV and V has been reported to be 9-39% and 0-9%, respectively.

Complications of endovascular embolization

Complications of endovascular embolization include persistent neurological deficits related to inadvertent embolization of arteries supplying normal brain tissue or obliteration of the venous outflow leading to intracerebral hemorrhages. The procedure carries an associated risk for morbidity and mortality in the range of 9-22% and 0-9%, respectively.

No long-term outcome studies are yet available; however, as endovascular techniques continue to improve, complication rates are likely to diminish.

Complications of radiosurgery

Complications depend on the size and location of the AVM. AVMs located in eloquent areas and in central locations are more prone to radiation-induced complications.

White matter edema and radiation-induced necrosis may occur during the 1- to 3-year treatment period. Persistent neurological deficits after radiation have been reported in 8% of treated patients.Patients with hemorrhagic presentation have a higher mean annual risk for hemorrhage until radiation-induced obliteration of the AVM is achieved compared to patients with a nonhemorrhagic presentation (6.3% vs 3.9%). The risk for hemorrhage seems to be lower after radiation therapy in patients with hemorrhagic presentation compared to the period before gamma knife radiotherapy was initiated.

Seizure frequency may increase in the first days to weeks after radiosurgery.

The potential for late effects from radiation, such as accelerated atherosclerosis in surrounding blood vessels, does exist.



With an overall risk of intracerebral hemorrhage of 2-4% per year, angiographic assessment is recommended to further define prognosis for patients with AVM.

Those with superficial, moderate-sized AVMs have a good long-term prognosis and may not have any additional benefit with interventional treatment.

Lifetime risk of hemorrhage may be substantial for young patients with AVM.

Prognosis after AVM hemorrhage is generally better than that after intracerebral hemorrhage from other causes. Better prognosis may be due to the relatively younger age of patients and a greater potential for reorganization of brain function. More accurate prognosis awaits the results of currently active, long-term, population-based outcome studies.


Patient Education

For excellent patient education resources, visit eMedicineHealth's Brain and Nervous System Center. Also, see eMedicineHealth's patient education article Stroke.