Reduced Serious Complication Rates from Embolo-sclerotherapy of Lower Extremity High and Low Flow Vascular Malformations from a Specialist Single Centre Over 5 Years

Abstract

Introduction - Therapeutic management of vascular malformations (VMs) often requires multiple interventions due to their recurrent nature. Embolosclerotherapy (EST) is the gold standard treatment for peripheral VMs including those of the lower extremities. Despite being minimally invasive, EST carries significant risk of serious complications when used for lower extremity VMs ischaemia, amputation, nerve injury, ulceration, thromboembolism and even death, with as high as 24% serious complication rates for foot treatment most recently reported (1). This study reviews 5-year serious complications following EST of all lower extremity VMs in our tertiary referral center for vascular anomalies. Methods - All VM patients underwent multidisciplinary review directed intervention, and demographic, procedural, follow-up and complication data collected prospectively in a dedicated database. Treatment outcomes for lower extremity VMs from 1 January 2013 to 31 December 2017 were analysed. All ESTs were performed under fluoroscopic guidance. All ESTs of high-flow vascular malformations (HFVM) were performed under selective catheter angiography and direct injection but low-flow vascular malformations (LFVM) with direct injection only. Serious complications were defined as any tissue or functional damage caused by direct injection, distal embolization or tissue reaction. Results - During the study period, 107 patients had a total of 168 interventional procedures; 160 (95.2%) ESTs, 4 (2.4%) surgical excisions, and 4 (2.4%) endothermal venous ablations and phlebectomies for lower extremity VMs. In this cohort of patients, the median (range) age was 26 (8-70) years; 42 males and 65 females. Of these, 18 patients (17%) had HFVM and 89 patients (83%) LFVM. These included 13 patients with Klippel-Trenaunay Syndrome (1 HFVM, 12 LFVM), one Mafucci’s Syndrome (HFVM) and one Milroy’s Disease (LFVM). Of the 160 ESTs, 86.25 (n=12 HFVM, n=72 LFVM) included the use of foam sclerotherapy, 8.12%(n=5HFVM and n=2 LFVM) alcohol, and 0.63% ( n=1 LFVM) coils. 5% of patients received a combination of sclerosants (e.g alcohol and coil, alcohol and STS). In total, 74.8% (n=80) of patients had clear clinical improvement and have been discharged since. Overall, 93.4% (100) of patients did not suffer from complications. 1.9% (n=2) of patients had non-serious complications characterized by excessive swelling. Meanwhile, 4.7% (n=5) of patients experienced serious complications:HFVM: 1 cellulitisLFVM: 2 skin ulcerations (Figure1), 1 cellulitis and 1 deep vein thrombosis (DVT) All the complications resolved with conservative and medical treatment without significant long-term physical and/or functional disability although the single DVT case required prolonged anticoagulant therapy. Conclusion - Currently, EST remains to be the interventional treatment of choice and is relatively safe and effective for lower extremity VMs. Our serious complication rate of 4.7% compares favorably to 11-24% in recent literature on peripheral VMs EST (2). This is possibly due to selective use of foam sclerotherapy versus alcohol, and improved classification and targeted treatment. Majority of the complications were due to local toxicity after direct injection. These outcomes will direct treatment strategies to avoid local toxic complications in the lower extremities for both HFVM and LFVM, and informing consent.