Expert review on the VenaSeal® system for endovenous cyano-acrylate adhesive ablation of incompetent saphenous trunks in patients with varicose veins

Cyanoacrylate Glue for Treating Chronic Saphenous Vein Insufficiency: A Retrospective Observational Single-Center Study

Endovenous thermal methods are superseding surgical stripping for treating chronic superficial venous disease but require tumescent anesthesia and can cause heat-related nerve injuries. Endovenous cyanoacrylate ablation is a more recent technique that does not share these drawbacks. A retrospective observational study of consecutive adults managed with endovenous cyanoacrylate was conducted in 2018-2021 at a single university center. The follow-up was 18 months. We identified factors associated with target vein closure at 18 months and measured changes in quality of life using the generic 36-item Short-Form (SF-36) tool and the venous disease-specific VEINES-QOL/Sym questionnaire. Adverse events were collected. In the 55 study patients with 67 treated veins, the closure rate at 18 months was 94% (95% CI, 85-98%). Target vein diameter ≥9.5 mm had 81% sensitivity and 75% specificity for predicting recanalization. Quality-of-life scores improved significantly (p < 0.001 for both surveys). The only adverse event was a type IV allergic reaction to cyanoacrylate that was resolved with corticosteroid and histamine-antagonist therapy. Endovenous cyanoacrylate ablation was highly effective and is safe in experienced hands. Studies are warranted to determine whether changes in the protocol increase the closure rate in patients with target veins ≥9.5 mm in diameter.

Current Best Practice in the Management of Varicose Veins

This article outlines the current best practice in the management of varicose veins. “Varicose veins” traditionally means bulging veins, usually seen on the legs, when standing. It is now a general term used to describe these bulging veins, and also underlying incompetent veins that reflux and cause the surface varicose veins. Importantly, “varicose veins” is often used for superficial venous reflux even in the absence of visible bulging veins. These can be simply called “hidden varicose veins”. Varicose veins usually deteriorate, progressing to discomfort, swollen ankles, skin damage, leg ulcers, superficial venous thrombosis and venous bleeds. Patients with varicose veins and symptoms or signs have a significant advantage in having treatment over conservative treatment with compression stockings or venotropic drugs. Small varicose veins or telangiectasia without symptoms or signs can be treated for cosmetic reasons. However, most have underlying venous reflux from saphenous, perforator or local “feeding veins” and so investigation with venous duplex should be mandatory before treatment. Best practice for investigating leg varicose veins is venous duplex ultrasound in the erect position, performed by a specialist trained in ultrasonography optimally not the doctor who performs the treatment. Pelvic vein reflux is best investigated with transvaginal duplex ultrasound (TVS), performed using the Holdstock-Harrison protocol. In men or women unable to have TVS, venography or cross-sectional imaging is needed. Best practice for treating truncal vein incompetence is endovenous thermal ablation. Increasing evidence suggests that significant incompetent perforating veins should be found and treated by thermal ablation using the transluminal occlusion of perforator (TRLOP) approach, and that incompetent pelvic veins refluxing into symptomatic varicose veins in the genital region or leg should be treated by coil embolisation. Bulging varicosities should be treated by phlebectomy at the time of truncal vein ablation. Monitoring and reporting outcomes is essential for doctors and patients; hence, participation in a venous registry should probably be mandatory.

A systematic review and meta-analysis of mechanochemical endovenous ablation using Flebogrif for varicose veins: A summary of evidence

OBJECTIVE

In the present study, we reviewed and analyzed the currently available data on the Flebogrif device (Balton, Warsaw, Poland) to define its role in the global varicose vein treatment devices market.

METHODS

A systematic literature search was performed in MEDLINE, Embase, and the Cochrane Library. Studies were eligible if they had included patients treated using the Flebogrif for saphenous vein incompetence, had been reported in English, and had the full text available. The methodologic quality of the studies was assessed using the methodologic index for nonrandomized studies (MINORS) score. A random effects model was used to estimate the primary outcome of anatomic success, defined as the occlusion rate of the treated vein. The estimates are reported with the 95% confidence intervals (CIs). The secondary outcomes were clinical success, complication rate, pain during and after the procedure, and time to return to work.

RESULTS

A total of 392 patients are reported in the included studies. A total of 348 legs were treated with Flebogrif (in 6 patients both legs). A total of 50 patients/legs were treated with EVLA (Ammollo et al.). In conclusion, 348 Flebogrif procedures are performed in 392 patients. Four studies reported the 3-month anatomic success, and three studies reported the 12-month anatomic success. The pooled 3-month anatomic success rate was 95.6% (95% CI, 93.2%-98.0%). The 12-month anatomic success rate was 93.2% (95% CI, 90.3%-96.1%). The only major complication reported within 3 months was deep vein thrombosis, which developed in 0.3% of the patients. The minor complications of thrombophlebitis and hyperpigmentation had occurred in 13.3% to 14.5% and 3.3% to 10.0% of patients, respectively, within 3 months. The methodologic quality of the included studies was moderate.

CONCLUSIONS

Mechanochemical ablation using the Flebogrif device is a safe and well-tolerated procedure for the treatment of saphenous vein insufficiency. However, well-designed studies of sufficient sample size and follow-up are required to compare the effectiveness with other endovenous treatment modalities and define the definitive role of the Flebogrif device.

Endovenous cyanoacrylate ablation for chronic venous insufficiency and varicose veins among Asians

Introduction: Endovenous cyanoacrylate glue (CAG) ablation for the treatment of chronic venous insufficiency (CVI) and varicose veins has shown non-inferior outcomes with an excellent safety profile, high patient satisfaction rate, and excellent efficacy when compared to the gold standard of endothermal ablation. A review of the current literature for CAG use in CVI showed that most studies and longer-term data are from Caucasian-based populations, which are subject to different anatomical venous variations and socio-economical contexts. This review aimed to gather the current evidence for CAG use in Asian CVI patients. Methods: Asian studies for the use of CAG in CVI were included in this review. Successful ablation rates, quality of life improvement and novel complications such as glue hypersensitivity reactions are described, along with anatomical descriptions of superficial venous anatomy in study patients. Use of CAG in Singapore and Asia was addressed. Results: CAG has been gaining traction as an option for CVI treatment in Asians. In Singapore, it has been adopted with comparable low complication rates and significant improvement of quality of life after treatment. As we increase our understanding of the variations in venous anatomy in the Asian population, new techniques such as retrograde deployment of the device and use of CAG ablation for venous leg ulcers have been developed. Conclusion: Further robust evidence in terms of large randomised control trials along with costeffectiveness studies are needed to determine the true value of CAG ablation in the Asian setting.

Evaluating patient preferences for thermal ablation versus nonthermal, nontumescent varicose vein treatments

OBJECTIVE

To measure patient preferences for attributes associated with thermal ablation and nonthermal, nontumescent varicose vein treatments.

METHODS

Data were collected from an electronic patient preference survey taken by 70 adult participants (aged 20 years or older) at three Center for Vein Restoration clinics in New Jersey from July 19, 2019, through August 13, 2019. Survey participation was voluntary and anonymous (participation rate of 80.5% [70/87]). Patients were shown 10 consecutive screens that displayed three hypothetical treatment scenarios with different combinations of six attributes of interest and a none option. Choice-based conjoint analysis estimated the relative importance of different aspects of care, trade-offs between these aspects, and total satisfaction that respondents derived from different healthcare procedures. Market simulation analysis compared clusters of attributes mimicking thermal ablation and nonthermal, nontumescent treatments.

RESULTS

Of the six attributes studied, out-of-pocket (OOP) expenditures were the most important to patients (37.2%), followed by postoperative discomfort (17.1%), risk of adverse events (16.3%), time to return to normal activity (11.0%), number of injections (10.0%), and number of visits (8.4%). Patients were willing to pay the most to avoid postoperative discomfort ($68.9) and risk of adverse events ($65.8). The market simulation analysis found that, regardless of the level of OOP spending, 60% to 80% of respondents favored attribute combinations corresponding with nonthermal, nontumescent procedures over thermal ablation, and that less than 1% of participants would forgo either treatment under no cost sharing.

CONCLUSIONS

Patients are highly sensitive to OOP costs for minimally invasive varicose vein treatments. Market simulation analysis favored nonthermal, nontumescent procedures over thermal ablation.

VenaSeal closure despite allergic reaction to n-butyl cyanoacrylate

The VenaSeal closure system (Medtronic, Minneapolis, Minn) is a nonthermal, minimally invasive method for the treatment of superficial venous insufficiency using a proprietary n-butyl cyanoacrylate. We report the case of a 45-year-old woman who underwent right great saphenous vein closure with VenaSeal and subsequently had a biphasic reaction to n-butyl cyanoacrylate, confirmed on patch testing that had negative results for other cyanoacrylates. Despite the initial allergic response, which settled with antihistamines, follow-up duplex ultrasound imaging confirmed successful great saphenous vein closure, and the affected vein remained in situ without further complication.

Thrombosis Following Endovenous Glue Ablation

Endovenous glue ablation for lower limb varicose veins is growing in popularity due to its safety and efficacy. Of significant concern is glue-associated thrombus extension into deep veins. We present a case of thrombus extending into the common femoral vein following endovenous glue ablation for varicose veins with the VenaSealTM closure system (VCS; Medtronic). A 63-year-old man who presented with symptomatic varicose veins had incompetence of the saphenofemoral junction. He underwent endovenous glue ablation using VCS closure. At 1 month, improvement in varicosities was mirrored by duplex ultrasound confirmation of successful long saphenous vein ablation, but ultrasound indicated thrombus extending into the common femoral vein. This was managed by surveillance duplex and serial clinical observation, with spontaneous resolution at 12 months. With increasing use of VCS for varicose veins, it is likely that thrombotic complications of the deep veins will be encountered more frequently. It is time for formulation of guideline-based management of this complication.

Cyanoacrylate closure for peripheral veins: Consensus document of the Australasian College of Phlebology

Background

Cyanoacrylates are fast-acting adhesives used in procedural medicine including closure of superficial wounds, embolization of truncal vessels pre-operatively, vascular anomalies, visceral false aneurysms, endoleaks, gastrointestinal varices and gastrointestinal bleeding. More recently, catheter-directed cyanoacrylate adhesive closure was introduced as an alternative to endovenous thermal ablation (ETA) to occlude superficial veins of the lower limbs.

Objectives

To formulate policies for the safe and effective delivery of cyanoacrylate adhesive closure procedures in Australasia, based on current experience and evidence.

Methods

A panel of phlebologists including vascular surgeons, interventional radiologists, dermatologists and research scientists systematically reviewed the available data on cyanoacrylate products used in medicine and shared personal experience with the procedure. The reviewed material included bibliographic and biomedical data, material safety data sheets and data requested and received from manufacturers. Results and recommendations: Cyanoacrylate adhesive closure appears to be an effective treatment for saphenous reflux with occlusion rates at 36 months of 90–95%. We recommend a maximum dose of 10 mL of cyanoacrylate per treatment session. Serious complications are rare, but significant. Hypersensitivity to acrylates is reported in 2.4% of the population and is an important absolute contraindication to cyanoacrylate adhesive closure. 1 Post-procedural inflammatory reactions, including hypersensitivity-type phlebitis, occur in 10–20% of patients. 2 In the long term, cyanoacrylate adhesive closure results in foreign-body granuloma formation within 2–12 months of the procedure. We recommend against the use of cyanoacrylate adhesive closure in patients with uncontrolled inflammatory, autoimmune or granulomatous disorders (e.g. sarcoidosis). Caution should be exercised in patients with significant active systemic disease or infection and alternative therapies such as thermal ablation and foam sclerotherapy should be considered.

Conclusions

Cyanoacrylate adhesive closure appears to be an effective endovenous procedure, with short-term closure rates comparable to ETA and therefore greater efficacy than traditional surgery for treating superficial veins of the lower limbs. Ongoing data collection is required to establish the long-term safety.

Poly(Alkyl Glycidate Carbonate)s as Degradable Pressure-Sensitive Adhesives

Insertion of CO₂ into the polyacrylate backbone, forming poly(carbonate) analogues, provides an environmentally friendly and biocompatible alternative. The synthesis of five poly(carbonate) analogues of poly(methyl acrylate), poly(ethyl acrylate), and poly(butyl acrylate) is described. The polymers are prepared using the salen cobalt(III) complex catalyzed copolymerization of CO₂ and a derivatized oxirane. All the carbonate analogues possess higher glass-transition temperatures (T_g =32 to -5 °C) than alkyl acrylates (T_g =10 to -50 °C), however, the carbonate analogues (T_d ≈230 °C) undergo thermal decomposition at lower temperatures than their acrylate counterparts (T_d ≈380 °C). The poly(alkyl carbonates) exhibit compositional-dependent adhesivity. The poly(carbonate) analogues degrade into glycerol, alcohol, and CO₂ in a time- and pH-dependent manner with the rate of degradation accelerated at higher pH conditions, in contrast to poly(acrylate)s.