Clinical trial NCT04524793: Efficacy and Safety of Endovenous Microwave Ablations for Treatment of Varicose Veins in Singapore
Official title: Pilot Study to Investigate the Efficacy and Safety of Endovenous Microwave Ablations for Treatment of Varicose Veins in Singapore
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Venous Insufficiency
Varicose Veins
Vascular Diseases
Keywords: endovenous microwave ablation
Lead sponsor: Singapore General Hospital
Sponsor class: OTHER
First posted: 2020-08-24
Enrollment: 30
Sex: ALL
Minimum age (years): 21
Maximum age (years): 99
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to assess change in patient's symptoms before and after Endovenous Microwave Ablation (EMA) as treatment for varicose veins. At the same time, it is to evaluate the effectiveness of EMA and its treatment outcomes over a period of 1 year.

Detailed description: Healthy leg veins have valves that allow blood to move in one direction from the lower leg to the heart. These valves open when blood is flowing toward the heart and then quickly close to stop any backward flow. When veins weaken, their valves cannot close properly, causing reversal of blood flow in the vein or venous reflux. Venous reflux due to the incompetent valves in the superficial venous system is the most common form of venous insufficiency, also known as varicose veins. This happens most often in the veins closest to the skin; the superficial veins. Varicose veins may or may not have associated symptoms and can look like twisted, bulging, rope-like cords or even small spider veins. While sometimes asymptomatic, varicose veins can be associated with pain, aching or cramping in the legs, heaviness or a tired sensation, paresthesia, pruritus, edema, inflammation with superficial phlebitis or thrombophlebitis, ulceration, bleeding from ulcerated varicosities, ecchymosis from subcutaneous rupture of varicosities, and deep venous thrombosis from extension of superficial thrombophlebitis.

Venous insufficiency of lower extremities is a very common condition that is influenced by genetic and mechanical factors, and is a chronic and progressive disorder. Prevalence estimates vary widely by geographic location, with the highest reported rates in Western countries, including Western Europe and the United States. Prevalence estimates of varicose veins range from \<1% to up to 73% in females and 2% to up to 56% in males. The reported prevalence ranges presumably reflect differences in the population distribution of risk factors, accuracy in application of diagnostic criteria, and the quality and availability of medical diagnostic and treatment resources. Risk factors for venous insufficiency include older age, female gender and pregnancy, family history of venous disease, obesity and occupations associated with prolonged standing.

There are a number of treatment options available to subjects with varicose veins, including vein stripping surgery, and thermal ablation; for example, Endovenous laser ablation (EVLA), radiofrequency ablation (RFA), and sclerotherapy. Recent technological advances have also brought about new treatment methods that are non-thermal, non-tumescent (NTNT). These include Venaseal and Clarivein. The goal of each of these treatment regimens is to eliminate source of reflux in order to control the progression of the disease, improve symptoms, promote ulcer healing, and prevent recurrence or a combination of these. The latest treatment available uses microwave ablation, which is a sub-type of radiofrequency and has the same characteristics as radiofrequency ablation.

The aim of this study is to report a collaborative, prospective Singaporean experience using the ECO Varicose Veins Therapeutic Unit from ECO (Nanjing ECO Microwave System Co., Ltd) for Endovenous Microwave Ablation (EMA) to treat primary great and short saphenous vein reflux and to evaluate its safety, efficacy and performance.

Eligibility criteria: Inclusion Criteria:

* Age \>21 years, able to understand the requirements of the study and provide informed consent.
* C2 - C5 varicose veins / CVI
* Symptomatic primary GSV, SSV or AASV incompetence, with reflux \>0.5 seconds on colour duplex, including one or more of the following symptoms: aching, throbbing, heaviness, fatigue, pruritus, night cramps, restlessness, generalized pain or discomfort, swelling.
* Patients who has GSV, SSV AASV diameters of 3mm to 12mm in the standing postition.

Exclusion Criteria:

* Current DVT or history of DVT
* Recurrent varicose veins
* Pregnant patients
* Arterial disease (ABPI \<0.8)
* Sepsis
* Patients who are unwilling to participate
* Inability or unwillingness to complete questionnaires
* Adverse reaction to sclerosant or cyanoacrylate
* GSV, SSV or AASV severely tortuous
* Life expectancy \< 1 year
* Active treatment for malignancy other than non-melanoma skin cancer
* Current, regular use of systemic anticoagulation (e.g. warfarin, heparin)
* Daily us of narcotic analgesia or NSAIDS to control pain associated with venous disease

Primary outcomes:
measure: Technical Success at time of procedure
timeFrame: Immediately post-procedure
measure: Anatomical Success
timeFrame: 2 weeks to 12 months post-procedure
Secondary outcomes:
measure: Quality of Life score using EQ-5D questionnaire
timeFrame: Baseline, 2-weeks, 3 months, 6 months and 12 months
measure: Quality of life score using the Chronic Venous Insufficiency Questionnaire (CIVIQ)
timeFrame: Baseline, 2-weeks, 3 months, 6 months and 12 months
measure: Quality of life score using the Aberdeen Varicose Veins Questionnaire (AVVQ)
timeFrame: Baseline, 2-weeks, 3 months, 6 months and 12 months
measure: Clinical Change using Venous Clinical Severity Score (VCSS)
timeFrame: Baseline, 2-weeks, 3 months, 6 months and 12 months
measure: Time taken to return to work and normal activities
timeFrame: 10 days post-op
measure: Patient's satisfaction
timeFrame: 2-weeks, 3 months, 6 months and 12 months
measure: Pain score post-procedure
timeFrame: 10 days post-op
measure: Occulsion rates
timeFrame: 2-weeks, 3 months, 6 months and 12 months
Other outcomes:
Locations:
city: Singapore
country: Singapore
facility: Singapore General Hospital
Study officials:
affiliation: Singapore General Hospital
name: Tang Tjun Yip
role: PRINCIPAL_INVESTIGATOR
References:
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citation: Davies HO, Popplewell M, Darvall K, Bate G, Bradbury AW. A review of randomised controlled trials comparing ultrasound-guided foam sclerotherapy with endothermal ablation for the treatment of great saphenous varicose veins. Phlebology. 2016 May;31(4):234-40. doi: 10.1177/0268355515595194. Epub 2015 Jul 9.