Venous malformations (VMs) are among the most common vascular malformations, second in frequency only to port-wine stains, and they are the most common vascular malformations seen in multidisciplinary vascular anomalies referral centers.1 They are structural anomalies of the venous vasculature that are composed of ectatic or aberrant venous channels deficient in smooth muscle cells. Most VMs are evident at birth, but a notable minority of patients present for the first time later in childhood or as adults. Although not a tumor per se,2 VMs may expand disproportionately to somatic growth. Some cases, both hereditary and sporadic, are due to mutations in Tie-2, an endothelial cell tyrosine kinase receptor, but many VMs do not show this mutation and are presumably due to other somatic or germ-line mutations. The concept of ongoing clotting within VMs is not new3,4; however, an increased appreciation of the significance of clotting, its associated coagulopathy, and its delineation from Kasabach-Merritt phenomenon is relatively recent. Two reports in the Archives in 2008 helped to further characterize this coagulopathy.5,6
Maguiness S, Koerper M, Frieden I. Relevance of D-dimer Testing in Patients with Venous Malformations. Arch Dermatol. 2009;145(11):1321–1324. doi:10.1001/archdermatol.2009.297
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