Multidisciplinary treatment of extremity arteriovenous malformations.

Congenital vascular malformations (CVMs) are a complex group of lesions that arise by embryologic dysmorphogenesis without increased endothelial proliferation that leads to structural and functional anomalies of the vascular system characterized by a wide range of presenting symptoms and often unpredictable clinical course. A recent advancement in the diagnostic and treatment modalities has resulted in a better understanding of the pathophysiology and natural history of CVMs and improved management of these lesions. The multidisciplinary approach and diagnostic algorithm used to distinguish high-flow (HFVM) from low-flow vascular malformations (LFVM) have been validated as clinically applicable for making an accurate anatomic and hemodynamic diagnosis of CVMs; they serve as a basis for proper treatment selection and significantly facilitate communication among different medical specialists. Dynamic contrast-enhanced magnetic resonance imaging is able to definitively distinguish HFVM from LFVM with accuracy of approximately 84%. In inconclusive cases, confirmatory angiography is required. Symptomatic, diffuse, extensive, macrocystic LFVMs and LFVMs that involve multiple tissue planes and vital structures are best treated with foam sclerotherapy. Primary surgical resection is the treatment of choice for localized, septated, and microcystic LFVMs. The management of HFVMs is characterized by multimodal treatment including preoperative embolization followed by complete surgical resection or sclerotherapy of the remaining venous component. Treatment of extensive CVMs is palliative and goal oriented. Implementation of the proposed diagnostic protocols and therapeutic algorithms in a multidisciplinary setting results in favorable outcomes with acceptable complication rates in this challenging patient population.