Of the following statements about congenital arteriovenous malformations, which are correct?

A. Patients with complex congenital arteriovenous malformations should as early as possible undergo ligation of feeding vessels.

B. Embolizing large arteriovenous malformations has not been demonstrated to be beneficial.

C. The most common complications of a large arteriovenous fistula are symptoms of congestive heart failure, pain, ulceration, and cosmetic deformity

DISCUSSION: Complex congenital arteriovenous malformations are often one of the greatest challenges a surgeon may encounter. Management includes accurate diagnosis and determination of the extent of the lesion. The site of communication should be localized by arteriography; however, computed tomography (CT), magnetic resonance imaging (MRI), and duplex Doppler imaging may prove useful in the diagnosis of arteriovenous communications. Ideal surgical management includes closure of the fistula with restoration of arterial and venous continuity. Complex arteriovenous malformations require a multidisciplinary approach, including intra-arterial embolization in conjunction with surgical therapy. Indications for surgery include secondary ischemic complications and congestive heart failure, pain, nonhealing ulcers, and a cosmetic deformity. Ligation of feeding vessels is effective only temporarily, making further treatment, especially embolization, difficult or impossible. Preoperative embolization may allow surgical resection and reduce operative blood loss.