Prognostic variables and outcome in relation to different bleeding patterns in arteriovenous malformations

Area of Science:

• Neurosurgery
• Neurology
• Radiology

Background:

• Arteriovenous malformations (AVMs) are rare vascular malformations.
• Subarachnoid hemorrhage (SAH) is an uncommon bleeding pattern in ruptured AVMs.
• Understanding bleeding patterns is crucial for AVM management.

Purpose of the Study:

• To evaluate different bleeding patterns in AVM hemorrhages.
• To assess the impact of bleeding patterns on patient outcomes.
• To inform risk and treatment stratification for ruptured AVMs.

Main Methods:

• Retrospective analysis of 158 patients with ruptured AVMs (2002-2017).
• Comparison of bleeding patterns: intracerebral hemorrhage (ICH), SAH, or both (ICH+SAH).
• Multivariate logistic regression to identify predictors of poor outcome.

Main Results:

• ICH occurred in 48.7%, isolated SAH in 20.9%, and both in 30.4% of patients.
• AVMs with aneurysms (38.6%) often presented with ICH+SAH.
• SAH pattern was more frequent in infratentorial AVMs.
• Poor admission status (WFNS IV-V), eloquent location, infratentorial AVMs, and ICH+SAH predicted poor outcomes.

Conclusions:

• Bleeding patterns in AVM hemorrhage are influenced by angioarchitectural and hemodynamic factors.
• The presence of SAH component negatively predicts outcome.
• AVM-associated pre-nidal aneurysms may increase rupture risk, particularly with SAH in infratentorial locations.
• Findings should guide AVM treatment decisions and risk stratification.