Plain English Summary
Background and study aims
Ruptured abdominal aortic aneurysm is a life-threatening condition where the main blood vessel of the body (the aorta) has swollen over many years (often silent with no obvious symptoms) and burst, causing extensive bleeding. Many patients with this condition do not survive to reach hospital alive. Until recently there was only one way to repair the ruptured aneurysm. This involved major surgery with a large cut in the tummy and replacement of the diseased aorta with a plastic (Polyester) tube (open surgery). However, after this major emergency surgery only about half of the patients leave hospital alive. A new 'keyhole' technique of aneurysm repair, called endovascular repair, has made it possible to re-line the ruptured aorta using a stent introduced through two small cuts in the groin (endovascular repair). However, only about 60% of patients are anatomically suitable for endovascular repair. At present we do not know which of the treatments is best for people with this condition. Therefore, this study aims to find out whether a strategy of preferential emergency endovascular repair reduces both the mortality (death rate) and cost of ruptured abdominal aortic aneurysm.
Who can participate?
Patients over the age of 50 who are suspected of having ruptured abdominal aortic aneurysm after review in Accident and Emergency (or other hospital unit)
What does the study involve?
Participants are randomly allocated, in the emergency room, to either a strategy of endovascular repair if possible (endovascular strategy) or to the current standard care (immediate transfer to the operating theatre for emergency open surgery). Patients allocated to the endovascular strategy undergo a special X-ray scan (CT scan) to assess anatomical suitability and plan for endovascular repair. This causes a short delay before definitive repair can begin: the study finds out whether this delay is dangerous. Those patients not suitable for endovascular repair after CT scan are taken for standard open surgery and the others have endovascular repair. Participants' survival within 30 days of surgery is measured, which it is hoped will improve by 14% with the endovascular strategy. Survival at hospital discharge and after 12 months, the costs of each treatment, quality of life and cost-effectiveness are also measured. It is hoped that these will improve with endovascular repair.
What are the possible benefits and risks of participating?
Ruptured abdominal aortic aneurysm is an immediately life-threatening condition. Without an operation patients do not survive. Consequently, operations to save patients' lives are associated with major complications. However, it is very unlikely that research participants will suffer any additional pain, discomfort, distress or inconvenience beyond patients not participating in the research. Patients who have received an endovascular repair will continue to be monitored for device complications under standard NHS care.
Where is the study run from?
The study co-ordinating centre is based at the Vascular Surgery Research Group, Imperial College London. The study will be conducted in about 20 specialist hospital centres in the UK (and one large centre in Canada), which have already attained sufficient experience in using endovascular repair for ruptured aneurysms and can offer a routine service of emergency endovascular repair.
When is the study starting and how long is it expected to run for?
April 2009 to March 2017
Who is funding the study?
National Institute for Health Research Health Technology Assessment Programme (UK)
Who is the main contact?
1. Prof. Janet Powell
j.powell@imperial.ac.uk
2. Dr Pinar Ulug
improvetrial@imperial.ac.uk
Trial website
Contact information
Type
Scientific
Primary contact
Prof Janet Powell
ORCID ID
http://orcid.org/0000-0002-3905-1468
Contact details
Vascular Surgery Research Group
Imperial College London
Charing Cross Campus
St Dunstans Road
London
W6 8RP
United Kingdom
+44 (0)20 8846 7312
j.powell@imperial.ac.uk
Additional identifiers
EudraCT number
ClinicalTrials.gov number
NCT00746122
Protocol/serial number
HTA 07/37/64
Study information
Scientific title
Can emergency endovascular aneurysm repair (eEVAR) reduce mortality from ruptured abdominal aortic aneurysm (AAA)?
Acronym
IMPROVE
Study hypothesis
Ruptured abdominal aortic aneurysm is the bursting of the main blood vessel of the body (the aorta) in the belly, which causes death in over 85% of cases. An attempt at open surgical repair is made in less than half of those who arrive at hospital alive and of those receiving surgical repair only half will be alive at 30 days.
It is possible that application of new minimally invasive technology (endovascular aneurysm repair [EVAR]) would greatly improve the number of patients alive at 30 days. However not all patients are anatomically suitable for endovascular repair.
The principal research question is, to be addressed in a randomised clinical trial is:
Can a strategy of preferential endovascular repair of ruptured abdominal aortic aneurysm, versus the current practice of open surgical repair, significantly reduce the 30 day mortality of this condition?
Ethics approval
1. South Central - Berkshire Research Ethics Committee, 22/12/2008, ref: 08/H0505/173
2. Scotland A Research Ethics Committee, 19/12/2008, ref: 08/MRE00/90
3. University of Western Ontario Health Sciences Research Ethics Board (HSREB), 14/06/2011, ref: 17698
Study design
Randomised controlled multi-centre trial
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
Hospitals
Trial type
Treatment
Patient information sheet
Patient information can be found at: http://www1.imperial.ac.uk/biosurgerysurgicaltechnology/clinical_trials_outcomes/vasculardisease/clinicaltrials/improvetrial/healthcare_professionals/resources/
Condition
Abdominal aortic aneurysm
Intervention
The patients will be randomised to a strategy of EVAR if anatomically suitable (EVAR first) or to the standard emergency open surgery.
Intervention type
Procedure/Surgery
Phase
Drug names
Primary outcome measures
30-day mortality
Secondary outcome measures
As of 18/08/2016:
1. Mortality at 24-hour, in-hospital, and 1-year and 3-years after the rupture
2. Complications and re-interventions related to ruptured AAA repair in 1 year and 3 years
3. Major morbidity (stroke, myocardial infarction, renal or respiratory failure) in 1 year
4. Accuracy of clinical diagnosis of ruptured abdominal aortic aneurysm
5. Cost and Cost-effectiveness
Initial
1. Mortality at 24-hour, in-hospital, and 1-year after the rupture
2. Complications and re-interventions related to ruptured AAA repair in 1 year
3. Major morbidity (stroke, myocardial infarction, renal or respiratory failure) in 1 year
4. Accuracy of clinical diagnosis of ruptured abdominal aortic aneurysm
5. Cost-effectiveness
Overall trial start date
01/04/2009
Overall trial end date
31/03/2017
Reason abandoned
Eligibility
Participant inclusion criteria
1. Both males and females, over the age of 50 years
2. Clinical suspicion of ruptured abdominal aortic aneurysm after review in Accident and Emergency (or other hospital unit)
Participant type
Patient
Age group
Adult
Gender
Both
Target number of participants
600
Participant exclusion criteria
1. Patients with known connective tissue disorders (e.g., Marfan syndrome) where endovascular repair may not be beneficial
2. Patients with known previous repair of an abdominal aortic aneurysm, because procedures either open or endovascular are likely to be very complex and there are no guidelines for anatomical restriction to repair
3. Deeply unconscious and moribund patients since the chances of recovery are minimal
Recruitment start date
16/09/2009
Recruitment end date
21/07/2013
Locations
Countries of recruitment
Canada, United Kingdom
Trial participating centre
Imperial College London
London
W6 8RP
United Kingdom
Sponsor information
Organisation
Imperial College London (UK)
Sponsor details
Research Governance Office
Faculty of Medicine
G02 Sir Alexander Fleming Building
South Kensington Campus
London
SW7 2AZ
United Kingdom
Sponsor type
University/education
Website
Funders
Funder type
Government
Funder name
Health Technology Assessment Programme
Alternative name(s)
NIHR Health Technology Assessment Programme, HTA
Funding Body Type
government organisation
Funding Body Subtype
Federal/National Government
Location
United Kingdom
Results and Publications
Publication and dissemination plan
Publications and reporting is expected in early 2014 (short-term results) and 2017 (long-term results).
IPD sharing statement
The datasets generated during and/or analysed during the current study are/will be available upon request from mjs212@medschl.cam.ac.uk after approval by the Trial Management Committee.
Intention to publish date
01/09/2017
Participant level data
Available on request
Results - basic reporting
Publication summary
2009 protocol in: http://www.ncbi.nlm.nih.gov/pubmed/19464199
2009 protocol in: http://www.ncbi.nlm.nih.gov/pubmed/20184048
2014 results in: http://www.ncbi.nlm.nih.gov/pubmed/24418950
2014 results in: http://www.ncbi.nlm.nih.gov/pubmed/24469620
2014 results in: http://www.ncbi.nlm.nih.gov/pubmed/24485843
2015 results in: http://www.ncbi.nlm.nih.gov/pubmed/25627357
2015 results in: http://www.ncbi.nlm.nih.gov/pubmed/25855369
2015 results in: http://www.ncbi.nlm.nih.gov/pubmed/26104471
2015 results in: http://www.ncbi.nlm.nih.gov/pubmed/25981698
Publication citations
-
Protocol
Powell JT, Thompson SG, Thompson MM, Grieve R, Nicholson AA, Ashleigh R, Hassan T, Moore F, Walker A, Braithwaite BD, Hinchliffe RJ, Greenhalgh RM, Cheshire NJ, Howell SJ, Soong CV, The Immediate Management of the Patient with Rupture: Open Versus Endovascular repair (IMPROVE) aneurysm trial--ISRCTN 48334791 IMPROVE trialists., Acta Chir. Belg., 109, 6, 678-680.
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Results
Powell JT, Sweeting MJ, Thompson MM, Ashleigh R, Bell R, Gomes M, Greenhalgh RM, Grieve R, Heatley F, Hinchliffe RJ, Thompson SG, Ulug P, Endovascular or open repair strategy for ruptured abdominal aortic aneurysm: 30 day outcomes from IMPROVE randomised trial., BMJ, 2014, 348, f7661.
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Results
Powell JT, Hinchliffe RJ, Thompson MM, Sweeting MJ, Ashleigh R, Bell R, Gomes M, Greenhalgh RM, Grieve RJ, Heatley F, Thompson SG, Ulug P, Observations from the IMPROVE trial concerning the clinical care of patients with ruptured abdominal aortic aneurysm., Br J Surg, 2014, 101, 3, 216-24; discussion 224, doi: 10.1002/bjs.9410.
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Results
An endovascular strategy for suspected ruptured abdominal aortic aneurysm brings earlier home discharge but not early survival or cost benefits., Eur J Vasc Endovasc Surg, 2014, 47, 4, 333-334, doi: 10.1016/j.ejvs.2013.12.017.
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Powell JT, Time to IMPROVE the management of ruptured abdominal aortic aneurysm: IMPROVE trialists., Eur J Vasc Endovasc Surg, 2009, 38, 2, 237-238, doi: 10.1016/j.ejvs.2009.04.002.
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Results
IMPROVE Trial Investigators, The effect of aortic morphology on peri-operative mortality of ruptured abdominal aortic aneurysm, Eur Heart J, 2015, doi: 10.1093/eurheartj/ehu521.
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Results
Grieve R, Gomes M, Sweeting MJ, Ulug P, Hinchliffe RJ, Thompson MM, Thompson SG, Ashleigh R, Greenhalgh RM, Powell JT; IMPROVE trial investigators, Endovascular strategy or open repair for ruptured abdominal aortic aneurysm: one-year outcomes from the IMPROVE randomized trial, Eur Heart J, 2015, doi: 10.1093/eurheartj/ehv125.