An Investigation into the role of Matrix Metalloproteinases (MMPs) in Lower Limb Vascular Restenosis

ISRCTN ISRCTN35955220
DOI https://doi.org/10.1186/ISRCTN35955220
Secondary identifying numbers N0544170118
Submission date
29/09/2006
Registration date
29/09/2006
Last edited
20/04/2015
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Surgery
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year

Plain English summary of protocol

Not provided at time of registration

Contact information

Mr Kevin Varty
Scientific

Box 201
Dept of Surgery
Addenbrooke's NHS Trust
Cambridge
CB2 2QQ
United Kingdom

Study information

Study designRandomised controlled trial
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Hospital
Study typeTreatment
Scientific titleAn Investigation into the role of Matrix Metalloproteinases (MMPs) in Lower Limb Vascular Restenosis
Study objectivesDoes blocking enzymes in the wall of the artery - matrix metalloproteinases (MMPs) - prevent the artery from narrowing after angioplasty (balloon treatment) or surgery (bypass graft)?
Ethics approval(s)Not provided at time of registration
Health condition(s) or problem(s) studiedSurgery: Cardiovascular
InterventionPatients under the care of the Cambridge Vascular Unit undergoing femoro-popliteal angioplasty or femoro-popliteal/tibial bypass will be eligible for the study. The indication for intervention will be severe limb ischaemia (rest pain, ulceration, gangrene) or short distance claudication failing to respond to medical and exercise therapy.

Pre-procedural Noninvasive Assessments:
Following informed consent the degree of ischaemia will be measured using ankle brachial pressure index (ABPI) measurements and transcutaneous oxygen measurements (TcPO2). Arterial stiffness and Endothelial Function will also be determined by applying a pressure probe to the carotid and radial arteries in turn with concomitant ECG gating.

Percutaneous Angioplasty:
These procedures are routinely carried out as either day cases or with overnight stay. During the procedure two 40 ml blood samples will be taken for plasma MMP analysis, plus CRP level, cholesterol, U&Es, elastin breakdown products, elastase activity and genetic analyses. One 40 ml sample will be systemic venous blood taken from the venous access cannula inserted for the procedure. A second 40 ml sample will be taken from the femoral vein in the leg undergoing the procedure. This is blood returning from the treated leg, and is more likely to reflect the local MMP activity potentially related to restenosis. On the same day as the PTA procedure the patients will be commenced on the SDD/placebo medication in a double blind randomised design. One tablet (25 mgs SDD) twice per day. This will be continued for 24 weeks post procedure.

Post Procedure Follow Up:
Colour duplex ultrasound assessment of the angioplasty site will be used to document blood velocities across the lesion and percentage of restenosis. These measurement will take place in the Vascular Laboratory at the following intervals: 1, 6, 12, 24, 36, 52 weeks. At 24 and 52 weeks repeat blood samples will be taken.

Femoro-distal bypass:
The same pre-procedural assessments will be performed as for PTA. These assessments will be co-ordinated with the patients pre-clerking clinic visit, usually 1 week prior to surgery. During surgery 2 tissue samples will be taken. One will be an arterial wall biopsy, to be analysed for arterial tissue MMP status. This will be taken from the proximal anastomosis site as a small ellipse avoiding any stenosis/narrowing of the anastomosis. A second sample will be taken from the venous tissue used for the bypass for MMP analysis.

As soon as patients are taking oral medication post operatively (usually 12-24 hours) the SDD/placebo medication will be commenced. As for PTA this will be for 24 weeks.

Prior to discharge the graft will be scanned to establish baseline graft velocities and any early abnormalities. As with the PTA protocol, further graft monitoring for stenosis, ABPI, and TcPO2 measurements will occur at 6, 12 , 24, 36 and 52 weeks. Surveillance of vein grafts at these intervals is normal clinical practice. Blood samples will be taken at 24 and 52 weeks.
Intervention typeMixed
Primary outcome measure1. MMP activities SDD versus placebo
2. CRP levels
3. Endothelial function and re-stenosis
4. Arterial wall stiffness and re-stenosis.
Secondary outcome measuresNot provided at time of registration
Overall study start date18/07/2005
Completion date18/07/2008

Eligibility

Participant type(s)Patient
Age groupAdult
SexBoth
Target number of participants35 in each trial arm, ie 270
Key inclusion criteriaSerum samples collected at the time of vascular intervention (radiologist or surgeon). Follow up samples by vascular research fellow.

Arterial wall and vein biopsies taken at the time of surgery by operating surgeon.
Key exclusion criteria1. Patient unable to give informed consent
2. Age < 18 years
3. Pregnancy, planned pregnancy
4. Life expectancy less than 12 months
5. Inability to monitor the angioplasty site or graft with ultrasound for stenosis
6. Unable to take SDD (ie allergic reaction) or currently taking tetracyclines
7. Unable to take adjuvant treatment with antiplatelet/anticoagulant agent and statin
Date of first enrolment18/07/2005
Date of final enrolment18/07/2008

Locations

Countries of recruitment

  • England
  • United Kingdom

Study participating centre

Addenbrooke's NHS Trust
Cambridge
CB2 2QQ
United Kingdom

Sponsor information

Record Provided by the NHSTCT Register - 2006 Update - Department of Health
Government

The Department of Health, Richmond House, 79 Whitehall
London
SW1A 2NL
United Kingdom

Phone +44 (0)20 7307 2622
Email dhmail@doh.gsi.org.uk
Website http://www.dh.gov.uk/Home/fs/en

Funders

Funder type

Government

Cambridge Consortium - Addenbrooke's (UK), NHS R&D Support Funding

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryNot provided at time of registration
Publication and dissemination planNot provided at time of registration
IPD sharing plan