Early rerupture of cerebral arteriovenous malformations: beware the progressive hemispheric swelling.

While early rerupture of cerebral arteriovenous malformations (AVMs) may not be as rare as previously thought, its determinants and risk factors remain unknown. Impairment of the venous drainage of AVMs is a well known risk factor for rupture and has been linked with the development of perinidal cerebral edema. We propose that a significant proportion of early AVM reruptures are the result of post-hemorrhagic venous drainage impairment, which may manifest as refractory perihematomal edema. To support this hypothesis, an illustrative case of early AVM rerupture occurring 3 weeks following intracranial hemorrhage and heralded by progressive perinidal and perihematomal edema is presented. This finding should be viewed as a marker for unstable lesions with a high risk of imminent rerupture and should thus prompt a rapid definitive treatment for the AVM.