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Efficacy and Safety of Endovenous Microwave Ablations for Treatment of Varicose Veins in Singapore (MAESTRO)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT04524793
Recruitment Status : Active, not recruiting
First Posted : August 24, 2020
Last Update Posted : September 27, 2021
Information provided by (Responsible Party):
Singapore General Hospital

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.

Condition or disease Intervention/treatment Phase
Venous Insufficiency Varicose Veins Vascular Diseases Other: Questionnaires Other: Physical examinations Not Applicable

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.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 30 participants
Allocation: N/A
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Pilot Study to Investigate the Efficacy and Safety of Endovenous Microwave Ablations for Treatment of Varicose Veins in Singapore
Actual Study Start Date : May 9, 2020
Actual Primary Completion Date : June 30, 2021
Estimated Study Completion Date : December 2021

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Varicose Veins

Arm Intervention/treatment
Endovenous Microwave Ablations
Patients that have undergone Endovenous Microwave Ablation from ECO (Nanjing ECO Microwave System Co., Ltd) to treat primary great and short saphenous vein reflux
Other: Questionnaires
Questionnaires to assess the quality of life (EQ-5D, CVVQ, CIVIQ, AVVQ, Patient satisfaction survey)

Other: Physical examinations
GSV/SSV/AASV reflux, CEAP Classification (Clinical, Aetiological, Anatomical and Pathophysiology), Venous Clinical Severity Score (VCSS) and duplex ultrasound

Primary Outcome Measures :
  1. Technical Success at time of procedure [ Time Frame: Immediately post-procedure ]
    Occlusion of treated vein post-procedure

  2. Anatomical Success [ Time Frame: 2 weeks to 12 months post-procedure ]
    Anatomical success defined as occlusion of treated vessel, as determined by duplex ultrasound

Secondary Outcome Measures :
  1. Quality of Life score using EQ-5D questionnaire [ Time Frame: Baseline, 2-weeks, 3 months, 6 months and 12 months ]
    EQ-5D is used to assess quality of life based on Mobility, Self-care, Usual Activities, Pain/Discomfort and Anxiety, rated at 5 levels: no problems, slight problems, moderate problems, severe problems, unable to perform activity. Inputs from this questionnaire is used to observe for changes in quality of life overtime

  2. Quality of life score using the Chronic Venous Insufficiency Questionnaire (CIVIQ) [ Time Frame: Baseline, 2-weeks, 3 months, 6 months and 12 months ]
    CIVIQ-14 is a questionnaire based on three dimensions - pain, physical and psychological, based on a scale from 1 to 5 (no trouble, slight, moderate, considerable, severe). Based on inputs, Global Index Score (GIS) will be tabulated, ranging from 0 to 100 - the higher the value, the poorer the quality of life.

  3. Quality of life score using the Aberdeen Varicose Veins Questionnaire (AVVQ) [ Time Frame: Baseline, 2-weeks, 3 months, 6 months and 12 months ]
    To measure health status of varicose vein patients based on symptoms and impact on daily activities. A total score ranging from 0 to 100 will be tabulated, with 100 being worst quality of life

  4. Clinical Change using Venous Clinical Severity Score (VCSS) [ Time Frame: Baseline, 2-weeks, 3 months, 6 months and 12 months ]
    VCSS evaluates the severity of hallmarks of venous disease - 0 (none), 1 (Mild) , 2(Moderate), 3 (Severe).

  5. Time taken to return to work and normal activities [ Time Frame: 10 days post-op ]
    Patient will be given a diary to record the day when they return to work and normal activities.

  6. Patient's satisfaction [ Time Frame: 2-weeks, 3 months, 6 months and 12 months ]
    To rate satisfaction with overall teatment regime with a numerical scale of 0 (least satisfied) to 10 (most satisfied)

  7. Pain score post-procedure [ Time Frame: 10 days post-op ]
    Participants will record their pain score using the Visual Analogue Score (VAS) for pain. The scale ranges from 0 (no pain) to 10 (worst pain imaginable).

  8. Occulsion rates [ Time Frame: 2-weeks, 3 months, 6 months and 12 months ]
    Duplex ultrasound performed at specific timepoints to ensure that the treated vein is occluded.

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   21 Years to 99 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

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

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT04524793

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Singapore General Hospital
Singapore, Singapore, 169608
Sponsors and Collaborators
Singapore General Hospital
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Principal Investigator: Tang Tjun Yip Singapore General Hospital
Geza M, Gloviczki P. Venous Embryology and Anatomy. In: Bergan JJ, editor. The Vein Book: Elsivier Academic Press; 2007.

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Responsible Party: Singapore General Hospital Identifier: NCT04524793    
Other Study ID Numbers: 2020/2371
First Posted: August 24, 2020    Key Record Dates
Last Update Posted: September 27, 2021
Last Verified: September 2021
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Singapore General Hospital:
endovenous microwave ablation
Additional relevant MeSH terms:
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Vascular Diseases
Venous Insufficiency
Varicose Veins
Cardiovascular Diseases