Management and Outcomes of Patients with Isolated Superficial Vein Thrombosis under Real Life Conditions (INSIGHTS-SVT)

Abstract

WHAT THIS PAPER ADDS Isolated superficial vein thrombosis (SVT) is a common but underrated condition. This study shows that patients' risk profiles, clinical presentation, and treatment patterns are very heterogeneous. Patients with SVT bear a significant risk of recurrent venous thromboembolism and recurrent or extended SVT at three months despite a high rate of initial anticoagulation. While recognising the methodological limitations of the prospective observational study design, the results suggest a beneficial effect of fondaparinux vs. low molecular weight heparin in isolated SVT under clinical practice conditions, in line with previous controlled and observational studies.Objective: Management and outcomes of superficial vein thrombosis (SVT) are highly variable and not well described. Therefore, the INvestigating SIGnificant Health TrendS in the management of SVT (INSIGHTS-SVT) study collected prospective data under real life conditions. Methods: Prospective observational study of objectively confirmed acute isolated SVT. The primary outcome was a composite of symptomatic deep vein thrombosis (DVT), pulmonary embolism (PE), and extension or recurrence of SVT at three months. The primary safety outcome was clinically relevant bleeding. Results: A total of 1 150 patients were included (mean age 60.2 AE 14.7 years; 64.9% women; mean BMI 29.4 AE 6.3 kg/ m 2 ). SVT was below the knee in 54.5%, above the knee in 26.7%, above and below the knee in 18.8%. At baseline, 93.6% received pharmacological treatment (65.7% fondaparinux, 23.2% heparins, 4.3% direct oral anticoagulants [DOACs], 14.5% analgesics), 77.0% compression treatment, and 1.9% surgery; 6.4% did not receive any anticoagulation. The primary outcome occurred in 5.8%; 4.7% had recurrent or extended SVT, 1.7% DVT, and 0.8% PE. Clinically relevant non-major bleeding occurred in 1.2% and major bleeding in 0.3%. Complete clinical recovery of SVT was reported in 708 patients (62.4%). Primary outcome adjusted by propensity score and for treatment duration was lower with fondaparinux compared with low molecular weight heparin (4.4% vs. 9.6%; hazard ratio [HR] 0.51; 95% confidence interval [CI] 0.3 e 0.9; p ¼ .017). On multivariable analysis, associated factors for primary outcome included another SVT prior to the present SVT event (HR 2.3), age per year (HR 0.97), duration of drug treatment per week (HR 0.92), and thrombus length (HR 1.03). Conclusion: At three month follow up, patients with isolated SVT are at risk of thromboembolic complications (mainly recurrent or extended SVT), despite anticoagulation. In this real life study, about one third had received either heparins, oral anticoagulants, or no anticoagulation.

Recommendations from the ICM-VTE: General

“…A past history of SVT is an independent risk factor for future DVT or PE 274 . Recurrent SVT is associated with a 2.3 - 2.5-fold increased risk of further VTE 276,277 . The risk of VTE recurrence is equivalent to that after proximal DVT 278 , with an OR of 5.5 (95% CI, 4.8 – 6.4) compared to controls 279 .…”

Does eradication of superficial vein incompetence after superficial vein thrombosis reduce the risk of recurrence and of deep vein thrombosis? A pilot study evaluating clinical practice in Örebro county, Sweden

“…Superficial vein thrombosis was previously seen as benign and selflimiting, but studies show a correlation with an increased risk of venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE). [1][2][3][4] According to the European Society for Vascular Surgery (ESVS) guidelines on management of venous thrombosis, duplex ultrasound (DUS) examination is therefore recommended in ambiguous cases, where the SVT is more than 5 cm in length and in situations where DVT cannot be ruled out. 5 Evidence for treatment of SVT is currently inconclusive, especially regarding prevention of VTE.…”

Features of Superficial Vein Thrombosis in Patients With a Large Diameter of Great Saphenous Vein

“…However, it has become clear that SVT, DVT, and PE are related diseases that can occur simultaneously or sequentially [5,6]. In a metaanalysis by Minno et al, including 4358 patients in 22 studies, the prevalence of DVT was 18.1 % and 6.9 % of PE together with SVT [7,8]. Recent studies have provided evidence that SVT should be considered a form of venous thromboembolism (VTE) along with DVT and PE [9].…”

“…Clinical manifestations are often benign and self-limiting [1,13,15]. However, it is important to consider the high risk of other VTEs [7,8].…”