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Carotid And Vertebral Artery Transluminal Angioplasty Study
DOI 10.1186/ISRCTN01425573
ClinicalTrials.gov identifier
EudraCT number
Public title Carotid And Vertebral Artery Transluminal Angioplasty Study
Scientific title
Acronym CAVATAS Study
Serial number at source MC1
Study hypothesis Atherosclerosis of the carotid and vertebral arteries in the neck is an important cause of stroke and transient ischaemic attack (TIA). Previous randomised clinical trials have demonstrated that the risks of stroke are significantly reduced by carotid surgery in suitable patients with recent symptoms and severe carotid stenosis. However, surgery has the disadvantage of an incision in the neck which may lead to cranial or superficial nerve injury and wound complications. There is also a significant risk of a stroke caused by the operation and a small risk of myocardial infarction. Carotid surgery is often performed under general anaesthesia, adding further to the potential for complications. Treatment of carotid stenosis by new endovascular techniques using balloon dilation (angioplasty) or stenting avoids a surgical incision and uses only local anaesthetic, but the risks and benefits of endovascular treatment were uncertain. We therefore compared endovascular treatment with conventional treatment in a multicentre international randomised trial.
Lay summary
Ethics approval Not provided at time of registration
Study design Randomised controlled trial
Countries of recruitment United Kingdom
Disease/condition/study domain Cardiovascular diseases: Cerebrovascular disease
Participants - inclusion criteria For inclusion in the study patients had to have stenosis of the common carotid artery, carotid bifurcation, internal carotid artery or extracranial vertebral artery that investigators considered suitable for endovascular treatment.

Patients eligible for surgery and patients ineligible for surgery were studied and randomised as two separate groups.

Investigators included patients only if the best treatment was unclear i.e. patients were randomly assigned only if they and their carotid or vertebral stenosis were equally suitable for both endovascular treatment and the alternative treatment (surgery or best medical care).
Participants - exclusion criteria Exclusion criteria included patients unable or unwilling to undergo one of the alternative treatment strategies, or who were unable to give informed consent, or if they had a disabling stroke with no useful recovery of function within the region supplied by the treatable artery. Patients were not eligible for the study if angiography showed thrombus in the affected artery, severe intracranial stenosis beyond the skull base, or a stenosis unsuitable for endovascular treatment e.g. because of tortuous vascular anatomy. However, patients did not need to have catheter angiography if a reliable non-invasive investigation had confirmed stenosis. Patients were not excluded if contraindications were noted after random assignment. There was no age limit.
Anticipated start date 01/01/1992
Anticipated end date 31/07/1997
Status of trial Completed
Patient information material Patient information can be found at: http://www.ion.ucl.ac.uk/cavatas_icss/downloads/Infosheet.pdf
Target number of participants 561
Interventions 561 patients were entered in three arms of the trial between 1992 and July 1997. Patients with carotid stenosis suitable for surgery (n=504) were randomised between endovascular treatment and carotid surgery. Patients with carotid stenosis unsuitable for surgery (n=40) and patients with vertebral artery stenosis (n=17) were separately randomised between endovascular treatment and medical care alone. The data from these last 2 groups has not yet been published. The main analysis was restricted to the 504 patients with carotid stenosis randomised between endovascular treatment (n=251) or surgery (n=253). Stents were used in 55 (22%) randomised to endovascular treatment; the remainder were treated by balloon angioplasty alone. Patients were followed up by an independent neurologist.
Primary outcome measure(s) Survival free of disabling stroke
Secondary outcome measure(s) Any stroke or death within 30 days of treatment, myocardial infarction within 30 days of treatment, treatment-related cranial nerve palsy or haematoma requiring reoperation or prolonging hospital stay. Stenosis (>70%) and occlusion on ultrasound follow-up. Stroke during follow-up. Further treatment procedure. Quality of life and economic measures.
Sources of funding NHS Cardiovascular Disease and Stroke National Research and Development Programme
Trial website http://www.cavatas.com
Publications http://www.thelancet.com/journal/vol357/iss9270/full/llan.357.9270.original_research.16458.1
Contact name Prof  Martin M  Brown
  Address Department of Clinical Neurology
Institute of Neurology
Queen Square
  City/town London
  Zip/Postcode WC1N 3BG
  Country United Kingdom
  Tel +44 (0)20 7829 8753
  Fax +44 (0)20 7833 8613
  Email m.brown@ion.ucl.ac.uk
Sponsor Record Provided by the NHS R&D 'Time-Limited' National Programme Register - Department of Health (UK)
  Address The Department of Health
Richmond House
79 Whitehall
  City/town London
  Zip/Postcode SW1A 2NL
  Country United Kingdom
  Tel +44 (0)20 7307 2622
  Fax +44 (0)20 7307 2623
  Email dhmail@doh.gsi.org.uk
  Sponsor website: http://www.doh.gov.uk
Date applied 23/01/2004
Last edited 07/08/2007
Date ISRCTN assigned 23/01/2004
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