Arteriovenous malformations of the lower extremities (AVM) can present as simple or complex combined or syndromic forms (e.g. Parkes Weber Syndrome). We aimed to characterize the differences in clinical presentation and natural history of these potentially life and limb threatening congenital vascular malformations.
We conducted a retrospective analysis of a consecutive series of patients with AVM, who presented to a tertiary referral center in Switzerland between 2008 and 2018. Clinical baseline characteristics, D-dimer level and course were summarized and differences between simple, non-syndromic and combined or syndromic AVM determined. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using logistic regression models.
Overall, 506 patients were prospectively enrolled in the Bernese Congenital Vascular Malformation Registry, 31 (6%) with AVM. There were 16 women and 15 men with a mean age of 18 years at first diagnosis (1 month – 72 years). Simple AVM was present in 22 (71%), combined or syndromic AVM with limb overgrowth in 9 patients (29%), respectively. Common symptoms and signs were pain 25 (81%), swelling 21 (68%) and soft tissue hypertrophy 13 (42%). Among combined or syndromic patients, 3 patients died from wound infection with sepsis or disseminated intravascular coagulation with bleeding complications (intracranial hemorrhage and bleeding from extensive leg ulcers). Combined or syndromic patients presented more often with bleeding (67% vs. 5%; p<0.001), malformation related infection (44% vs. 5%; p=0,017) and leg length difference (56% vs. 14%; p=0.049). D-dimer levels were elevated (mean 17256 μg/L, range 1557 μg/L to 80000 μg/L) and angiographic appearance showed complex, mixed type of AVMs, including interstitial type IV, in all patients with combined or syndromic AVM.
Patients with congenital simple AVM most often present with benign clinical features and rarely complications related to hemodynamic changes. Patients with combined or syndromic AVM often face serious outcomesdominated by complications other than direct high flow related heart failure.

Copyright © 2021. Published by Elsevier Inc.

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