Objective: To assess the role of this procedure to prevent hemorrhage in cerebral arteriovenous malformations (cAVM).
Method: Between 1992 and 2000, we studied 104 patients submitted to embolization as the main treatment. Patients were followed until hemorrhage or death.
Results: Follow-up ranged from 1.6 months to 8 years. The most frequent presentations were hemorrhage (50%) and seizures (38%). In addition, 40% were small (<30 mm); 56% were medium (30-60 mm). Obliteration was < or =1/3 in 11% of the cases; from 1/3 to < or = 2/3 in 49%; >2/3 in 36%; complete in 5%. The risk of death was 1%/year, and of bleeding, 5.4%/year. Presentation with hemorrhage and low obliteration rate were the main factors associated with hemorrhage.
Conclusion: cAVM embolization provides limited protection against hemorrhage with obliteration rates below 2/3. Presentation with hemorrhage is the main factor for predicting hemorrhage.