Arteriovenous malformations are typically located in which organ?

Arteriovenous malformations are typically located in which organ?

• A. Lungs
• B. Heart
• C. Brain
• D. Liver

Answer: (C)

Arteriovenous malformations form when arteries connect directly to veins without the normal intervening capillary bed. This creates a high-flow, fragile vascular nidus that can rupture. The brain is the typical site because AVMs there are particularly clinically significant: a ruptured brain AVM can cause intracerebral or subarachnoid hemorrhage, seizures, or focal neurologic deficits. Patients may present with a sudden severe headache, new-onset seizures, or neurologic changes, and imaging reveals a tangled cluster of abnormal vessels in the brain parenchyma. Other organs can have AVMs, such as the lungs or liver, and those have important implications (pulmonary AVMs can cause hypoxemia and paradoxical emboli; hepatic AVMs can lead to high-output heart failure), but the brain remains the most commonly emphasized location given the serious neurologic consequences and the focus of many exam questions.

Arteriovenous malformations form when arteries connect directly to veins without the normal intervening capillary bed. This creates a high-flow, fragile vascular nidus that can rupture.

The brain is the typical site because AVMs there are particularly clinically significant: a ruptured brain AVM can cause intracerebral or subarachnoid hemorrhage, seizures, or focal neurologic deficits. Patients may present with a sudden severe headache, new-onset seizures, or neurologic changes, and imaging reveals a tangled cluster of abnormal vessels in the brain parenchyma.

Other organs can have AVMs, such as the lungs or liver, and those have important implications (pulmonary AVMs can cause hypoxemia and paradoxical emboli; hepatic AVMs can lead to high-output heart failure), but the brain remains the most commonly emphasized location given the serious neurologic consequences and the focus of many exam questions.