CASS (CyanoAcrylate closure versus Surgical Stripping for incompetent saphenous veins) study: a randomized controlled trial comparing clinical outcomes after cyanoacrylate closure and surgical stripping for the treatment of incompetent saphenous veins

Complex Hypersensitivity and Irritation Reaction (CHAIR) Phenomenon after Cyanoacrylate Closure of Varicose Vein

Cyanoacrylate glue is a non-thermal, non-tumescent agent used to treat saphenous reflux. It was introduced to overcome heat-related discomfort and complications. Multiple randomized controlled trials using this therapy have demonstrated excellent clinical outcomes at long-term follow-up. However, diffuse injection-site inflammation and systemic urticaria are worrisome complications. In preclinical studies, serial histopathological findings demonstrated acute inflammatory reaction, subacute vasculitis, chronic granulomatous foreign body reaction, fibrotic changes with partial vascular recanalization, and chronic foreign body-type inflammatory response. While the exact nature of this unique complication remains undefined, complex hypersensitivity and irritation reaction phenomena have been suggested based on reported clinical presentations. The incidence of this complication has been reported as ranging from 0.3%-25.4%. Typically, erythematous reactions can occur near treatment sites, with symptoms ranging from mild pruritus and/or erythema that resolves without treatment to recurrent severe inflammation and pruritus requiring nonsteroidal anti-inflammatory drugs, antihistamines, and/or corticosteroids. Surgical excision has been rarely reported in patients with severe intractable inflammation or treatment-site infections. Although several anecdotal studies reported on using antihistaminics or corticosteroids, no effective strategies have been established to prevent this complication.

A multicenter randomized controlled trial of cyanoacrylate closure and surgical stripping for incompetent great saphenous veins

OBJECTIVE

The treatment of varicose veins has shifted from conventional surgical stripping (SS) to minimally invasive endovenous modalities. Cyanoacrylate closure (CAC) with the VenaSeal system (Medtronic, Dublin, Ireland) has increased in popularity owing to its nonthermal and nontumescent technique. The purpose of the present study was to compare the clinical outcomes of CAC and SS for the treatment of incompetent great saphenous veins.

METHODS

An open-label, multicenter, prospective, randomized controlled trial was conducted. The subjects were randomized to either the CAC or SS procedure. The primary endpoint of the present study was to evaluate complete closure of the target vein at 3 months. Target vein occlusion was assessed on the third day and 1, 3, 6, and 12 months postoperatively using duplex ultrasound. The pain and ecchymosis grades were also assessed. Additionally, the clinical outcomes, such as the venous clinical severity score and Aberdeen Varicose Vein Questionnaire score, were assessed.

RESULTS

Three-month follow-up data were obtained for all 126 enrolled and randomized subjects (63 with CAC and 63 with SS). At 3 months, complete target vein closure was observed in both groups. The postoperative pain score was significantly better in the CAC group than in the SS group (0.3 ± 0.6 in the CAC group and 1.1 ± 1.5 in the SS group; P < .001). In addition, the mean ecchymosis grade was 0.3 ± 0.5 in the CAC group and 1.1 ± 1.1 in the SS group (P < .001). The venous clinical severity score and quality of life had improved equally in both groups. The adverse events after both procedures were mostly minor complications (9 events in CAC group and 20 events in SS group). Major complications occurred in one patient who had undergone the SS procedure.

CONCLUSIONS

The CAC and SS procedures were both associated with complete occlusion of the target vein at 3 months. The postoperative pain and ecchymosis grades were significantly lower in the CAC group. Other differences between the two groups included the frequency and nature of the complications. The results showed that CAC has high success with few complications.

Interventions for great saphenous vein incompetence

BACKGROUND

Great saphenous vein (GSV) incompetence, causing varicose veins and venous insufficiency, makes up the majority of lower-limb superficial venous diseases. Treatment options for GSV incompetence include surgery (also known as high ligation and stripping), laser and radiofrequency ablation, and ultrasound-guided foam sclerotherapy. Newer treatments include cyanoacrylate glue, mechanochemical ablation, and endovenous steam ablation. These techniques avoid the need for a general anaesthetic, and may result in fewer complications and improved quality of life (QoL). These treatments should be compared to inform decisions on treatment for varicosities in the GSV. This is an update of a Cochrane Review first published in 2011.

OBJECTIVES

To assess the effects of endovenous laser ablation (EVLA), radiofrequency ablation (RFA), endovenous steam ablation (EVSA), ultrasound-guided foam sclerotherapy (UGFS), cyanoacrylate glue, mechanochemical ablation (MOCA) and high ligation and stripping (HL/S) for the treatment of varicosities of the great saphenous vein (GSV).

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, and AMED databases, and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 2 November 2020. We undertook reference checking to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) treating participants for varicosities of the GSV using EVLA, RFA, EVSA, UGFS, cyanoacrylate glue, MOCA or HL/S. Key outcomes of interest are technical success, recurrence, complications and QoL.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, applied Cochrane's risk of bias tool, and extracted data. We calculated odds ratios (ORs) with 95% confidence intervals (CIs) and assessed the certainty of evidence using GRADE.

MAIN RESULTS

We identified 11 new RCTs for this update. Therefore, we included 24 RCTs with 5135 participants. Duration of follow-up ranged from five weeks to eight years. Five comparisons included single trials. For comparisons with more than one trial, we could only pool data for 'technical success' and 'recurrence' due to heterogeneity in outcome definitions and time points reported. All trials had some risk of bias concerns. Here we report the clinically most relevant comparisons. EVLA versus RFA Technical success was comparable up to five years (OR 0.98, 95% CI 0.41 to 2.38; 5 studies, 780 participants; moderate-certainty evidence); over five years, there was no evidence of a difference (OR 0.85, 95% CI 0.30 to 2.41; 1 study, 291 participants; low-certainty evidence). One study reported recurrence, showing no clear difference at three years (OR 1.53, 95% CI 0.78 to 2.99; 291 participants; low-certainty evidence), but a benefit for RFA may be seen at five years (OR 2.77, 95% CI 1.52 to 5.06; 291 participants; low-certainty evidence). EVLA versus UGFS Technical success may be better in EVLA participants up to five years (OR 6.13, 95% CI 0.98 to 38.27; 3 studies, 588 participants; low-certainty evidence), and over five years (OR 6.47, 95% CI 2.60 to 16.10; 3 studies, 534 participants; low-certainty evidence). There was no clear difference in recurrence up to three years and at five years (OR 0.68, 95% CI 0.20 to 2.36; 2 studies, 443 participants; and OR 1.08, 95% CI 0.40 to 2.87; 2 studies, 418 participants; very low-certainty evidence, respectively). EVLA versus HL/S Technical success may be better in EVLA participants up to five years (OR 2.31, 95% CI 1.27 to 4.23; 6 studies, 1051 participants; low-certainty evidence). No clear difference in technical success was seen at five years and beyond (OR 0.93, 95% CI 0.57 to 1.50; 5 studies, 874 participants; low-certainty evidence). Recurrence was comparable within three years and at 5 years (OR 0.78, 95% CI 0.47 to 1.29; 7 studies, 1459 participants; and OR 1.09, 95% CI 0.68 to 1.76; 7 studies, 1267 participants; moderate-certainty evidence, respectively). RFA versus MOCA There was no clear difference in technical success (OR 1.76, 95% CI 0.06 to 54.15; 3 studies, 435 participants; low-certainty evidence), or recurrence (OR 1.00, 95% CI 0.21 to 4.81; 3 studies, 389 participants; low-certainty evidence). Long-term data are not available. RFA versus HL/S No clear difference in technical success was detected up to five years (OR 5.71, 95% CI 0.64 to 50.81; 2 studies, 318 participants; low-certainty evidence); over five years, there was no evidence of a difference (OR 0.88, 95% CI 0.29 to 2.69; 1 study, 289 participants; low-certainty evidence). No clear difference in recurrence was detected up to three years (OR 0.93, 95% CI 0.58 to 1.51; 4 studies, 546 participants; moderate-certainty evidence); but a possible long-term benefit for RFA was seen (OR 0.41, 95% CI 0.22 to 0.75; 1 study, 289 participants; low-certainty evidence). UGFS versus HL/S Meta-analysis showed a possible benefit for HL/S compared with UGFS in technical success up to five years (OR 0.32, 95% CI 0.11 to 0.94; 4 studies, 954 participants; low-certainty evidence), and over five years (OR 0.09, 95% CI 0.03 to 0.30; 3 studies, 525 participants; moderate-certainty evidence). No clear difference was detected in recurrence up to three years (OR 1.81, 95% CI 0.87 to 3.77; 3 studies, 822 participants; low-certainty evidence), and after five years (OR 1.24, 95% CI 0.57 to 2.71; 3 studies, 639 participants; low-certainty evidence). Complications were generally low for all interventions, but due to different definitions and time points, we were unable to draw conclusions (very-low certainty evidence). Similarly, most studies evaluated QoL but used different questionnaires at variable time points. Rates of QoL improvement were comparable between interventions at follow-up (moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Our conclusions are limited due to the relatively small number of studies for each comparison and differences in outcome definitions and time points reported. Technical success was comparable between most modalities. EVLA may offer improved technical success compared to UGFS or HL/S. HL/S may have improved technical success compared to UGFS. No evidence of a difference was detected in recurrence, except for a possible long-term benefit for RFA compared to EVLA or HL/S. Studies which provide more evidence on the breadth of treatments are needed. Future trials should seek to standardise clinical terminology of outcome measures and the time points at which they are measured.