Introduction High grade cerebral AVM (Spetzler grade 4 and 5) have a very complex structure and architecture. Accordingly, their management is very challenging. Their natural history also is known to be poor. We present our experience of patients with high-grade cerebral AVM and their management with endovascular methods.

Methods Sixty-seven patients with high-grade cerebral AVM with one embolization session between 2010 and 2021 were included in this study. The baseline and treatment outcomes were collected and reported.

Results The mean age of patients was 29.2 years ± 15.8 (SD) with predominant of men (63.6%). The most common presentations were hemorrhage (57.6%), seizure (18.2%), and focal neurological deficit (13.6%). At patient admission, median range of modified Rankin scale was 1 (range of 0 to 4). The majority of AVMs were located in cortical and subcortical area (47%), 53 were grade 4 of Spetzler- Martin, and 14 grade 5. Mean nidus diameter was 47.8 mm ± 14.2 (SD). Median number of embolization sessions was 3 with range of 1-13. Eighteen AVMs (26.9%) were completely excluded by embolization (33% in grade 4 and 7% in grade 5). Significant complications occurred in 24 (36%) patients including hemorrhage (66.7%) and ischemia (33.3%). Fifty patients (75.8%) had good outcome (mRs 0-2) and one patient died following embolization.

Conclusion Despite relative high rate of complications, the majority of our patients had good outcome that is better than natural history of the high grade cerebral AVMs. Complete exclusion of high-grade cerebral AVM could be achieved by embolization in limited patients. Further studies are needed to define the optimal management for these complex AVMs.

Disclosures H. Baharvahdat: None. R. Blanc: None. S. Escalard: None. J. Desilles: None. H. Redjem: None. F. Delvoye: None. S. Smajda: None. A. Al Raaisi: None. W. Boisseau: None. M. Mazighi: None. M. Piotin: None.