A large nationwide survey conducted by the Japanese Regulatory Committee for Endovascular Treatment of Varicose Veins has demonstrated that cyanoacrylate closure (CAC) for varicose veins is safe with low rates of serious adverse events, such as venous thromboembolism.
CAC is a minimally invasive technique for treating axial venous reflux; however, the incidence of serious adverse events related to the procedure is “concerning”, stated lead author Michihisa Umetsu (Tohoku University Hospital, Miyagi, Japan) et al. Due to an increasing number of patients undergoing CAC and insufficient data in Japan, the authors sought to investigate the safety profile of the procedure, tracking type and incidence of adverse events.
Umetsu et al collected data pertaining to 24,209 patients who underwent CAC at 335 institutions between January 2020 and October 2023. The authors highlight that the present cohort represents 73% of all CACs performed in Japan. Thromboembolism, phlebitis, hypersensitivity reactions, granuloma formation, infection, bleeding, death, and need for glue resection were documented as unfavourable events or outcomes.
Venous thromboembolism was reported in 142 (0.59%) patients, pulmonary embolism (PE), proximal deep vein thrombosis and ablation-related thrombosis extension developed in three (0.01%), nine (0.04%), and 95 (0.39%) patients, respectively. Localised phlebitis that required additional treatment was observed in 1,656 patients (6.8%). Of the localised hypersensitivity cases, 960 (58%) required oral antihistamines and 268 (16%) required oral and/or intravenous steroids. Furthermore, 65 patients (0.27%) developed systemic hypersensitivity that required systemic steroids. No patients developed a stroke or anaphylaxis; however, one patient died due to PE.
Umetsu and colleagues state that glue resection was performed in nine patients with delayed infection, hypersensitivity reactions or a foreign body granuloma. The incidence of hypersensitivity reactions was similar among institutions, the authors note; however, the incidence of thrombosis-related events “significantly differed” between high- and low-volume institutions. The incidence of proximal deep vein thrombosis (0.13% vs. 0.01%; p<0.001; odds ratio [OR], 12.5; 95% confidence interval [CI], 2.6–60.3) and ablation-related thrombus extension (0.73% vs. 0.30%; p<0.001; OR, 2.5; 95% CI, 1.66–3.77) was significantly higher in low-volume institutions than in high-volume centres, Umetsu et al state.
In their discussion, Umetsu and colleagues highlight that CAC represents a less invasive treatment modality compared to conventional endovenous thermal ablation (EVTA) in this patient population. They highlight that the risks of nerve injury and skin burns that can occur with EVTA can be avoided with CAC, while hypersensitivity to CAC—the most common adverse event associated with the procedure—does not occur with EVTA.
“Most of the reactions observed in our study population seemed to be transient, although a few were prolonged. The incidence of hypersensitivity reactions requiring systemic steroids varied among the institutions in this study, ranging from 0% to 50%. Some institutions treated less than 20% of their patients with steroids, potentially causing an overestimation of the hypersensitivity rates,” state Umetsu et al.
While the authors note that the present survey was not conducted to determine the superiority of treatments, and state that CAC would not replace conventional EVTA for saphenous veins, they conclude that the former can be optimised for treatment in select patients. Given their large sample size, Umetsu and colleagues emphasise that their survey provides a “highly accurate” report of the national incidence of adverse events associated with CAC.
