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Updated: May 31, 2026
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Comprehensive Endovascular and Open Surgical Management of Cerebral Arteriovenous Malformations
Published on: October 20, 2017
Alterations in systemic complement component 3a and 5a levels in patients with cerebral arteriovenous malformations
Raqeeb Haque1, Brian Y Hwang, Geoffrey Appelboom
1Department of Neurological Surgery, Columbia University Medical Center, 710 West 168th Street, Room 431, New York 10032, USA.
Summary
Systemic levels of C3a and C5a, key inflammatory mediators, are elevated in cerebral arteriovenous malformation (AVM) patients. Treatment via embolization significantly reduces these complement factors, indicating their role in AVM pathophysiology.
Area of Science:
- Neuroscience
- Immunology
- Vascular Biology
Background:
- The role of the complement cascade in cerebral arteriovenous malformation (AVM) pathophysiology is not well understood.
- Complement subcomponents C3a and C5a are potent anaphylatoxins and key mediators of immuno-inflammatory responses.
- Complement activation may contribute to the pro-inflammatory state observed in AVM.
Purpose of the Study:
- To determine the systemic levels of C3a and C5a in patients with AVM.
- To investigate the response of C3a and C5a levels to AVM treatments, including embolization and resection.
Main Methods:
- Plasma concentrations of C3a and C5a were measured using enzyme-linked immunosorbent assay (ELISA).
- Blood samples were collected from 18 patients with unruptured AVM and 30 healthy controls at four time points: pre-treatment, 24-hours post-embolization, 24-hours post-resection, and 1-month follow-up.
Main Results:
- Pre-treatment plasma C3a and C5a levels were significantly higher in AVM patients compared to controls.
- Mean C3a and C5a levels decreased significantly 24 hours after embolization.
- These reduced levels remained statistically similar after resection and at 1-month follow-up, but were still higher than control levels.
Conclusions:
- Systemic C3a and C5a levels are elevated at baseline in patients with cerebral AVM.
- Embolization treatment leads to a significant decrease in these complement factors.
- Elevated C3a and C5a levels suggest a role for the complement cascade in AVM pathophysiology and indicate treatment response.
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