Arteriovenous Malformations (AVMs) and Associated Conditions

Primary Associated Genetic Conditions

The American Heart Association suggests that hereditary hemorrhagic telangiectasia (HHT) should be considered in any patient presenting with multiple AVMs of the nervous system, as this represents the most significant genetic association 2
AVMs have been inconsistently described as features of various other genetic conditions, though specific syndromes are not well-characterized in the guidelines from the American Stroke Association 2
The American College of Medical Genetics recommends that TNF-α-238 AG genotype and ApoE ε2 carrier status are independent risk factors for hemorrhage in patients with AVMs 3

The American Heart Association notes that the occurrence of an aneurysm and an AVM in the same individual is more common in children than in adults 2
Presence of intranidal aneurysms or feeding artery aneurysms increases the risk of hemorrhage, according to the British Society of Neurosurgeons 3, 4
Multiple aneurysms can coexist with AVMs and represent important risk factors for bleeding, as stated by the American Association of Neurological Surgeons 3

More than 50% of AVMs present with intracranial hemorrhage, which can be intracerebral, subarachnoid, or intraventricular, according to the American Heart Association 5
The annual hemorrhage risk is 2-4% with mortality from first hemorrhage between 10-30%, as reported by the American Stroke Association 3, 5, 4
Seizures occur in approximately 20-25% of AVM cases and may be focal or generalized, according to the American Academy of Neurology 5, 4

Symptomatic neonates often present with unexplained high-output cardiac failure, and these patients tend to fare much worse than those presenting later, as noted by the American Academy of Pediatrics 2
An estimated 20% of cerebral AVMs are diagnosed during infancy and childhood, according to the American Heart Association 2, 6

The American Thoracic Society lists trauma, chest surgery, certain infections, and hepatopulmonary syndrome as secondary causes of pulmonary AVMs 1

Pregnancy may be associated with rapid growth of pulmonary AVMs due to hormonal changes, requiring heightened surveillance, as recommended by the American College of Obstetricians and Gynecologists 1
Severe vasospasm from AVM-related hemorrhage is distinctly uncommon, unlike aneurysmal subarachnoid hemorrhage, according to the American Stroke Association 5