title: Temporal trends in safety of carotid endarterectomy in asymptomatic patients: systematic review.
abstract: OBJECTIVE
  To systematically review temporal changes in perioperative safety of carotid endarterectomy (CEA) in asymptomatic individuals in trial and registry studies.
  
  
  METHODS
  The MEDLINE and EMBASE databases were searched using the terms "carotid" and "endarterectomy" and "asymptomatic" from 1947 to August 23, 2014. Articles dealing with 50%-99% stenosis in asymptomatic individuals were included and low-volume studies were excluded. The primary endpoint was 30-day stroke or death and the secondary endpoint was 30-day all-cause mortality. Statistical analysis was performed using random-effects meta-regression for registry data and for trial data graphical interpretation alone was used.
  
  
  RESULTS
  Six trials (n = 4,431 procedures) and 47 community registries (n = 204,622 procedures) reported data between 1983 and 2013. Registry data showed a significant decrease in postoperative stroke or death incidence over the period 1991-2010, equivalent to a 6% average proportional annual reduction (95% credible interval [CrI] 4%-7%; p < 0.001). Considering postoperative all-cause mortality, registry data showed a significant 5% average proportional annual reduction (95% CrI 3%-9%; p < 0.001). Trial data showed a similar visual trend.
  
  
  CONCLUSIONS
  CEA is safer than ever before and high-volume registry results closely mirror the results of trials. New benchmarks for CEA are a stroke or death risk of 1.2% and a mortality risk of 0.4%. This information will prove useful for quality improvement programs, for health care funders, and for those re-examining the long-term benefits of asymptomatic revascularization in future trials.
authors.affiliation: From the Academic Section of Vascular Surgery (A.B.M., M.I.Q., A.T., A.H.D.), Imperial College London; and the Department of Non-communicable Disease Epidemiology (A.J.F.), London School of Hygiene and Tropical Medicine, UK.
authors.forename: Alex B
authors.initials: AB
authors.lastname: Munster
authors.affiliation: From the Academic Section of Vascular Surgery (A.B.M., M.I.Q., A.T., A.H.D.), Imperial College London; and the Department of Non-communicable Disease Epidemiology (A.J.F.), London School of Hygiene and Tropical Medicine, UK.
authors.forename: Angelo J
authors.initials: AJ
authors.lastname: Franchini
authors.affiliation: From the Academic Section of Vascular Surgery (A.B.M., M.I.Q., A.T., A.H.D.), Imperial College London; and the Department of Non-communicable Disease Epidemiology (A.J.F.), London School of Hygiene and Tropical Medicine, UK.
authors.forename: Mahim I
authors.initials: MI
authors.lastname: Qureshi
authors.affiliation: From the Academic Section of Vascular Surgery (A.B.M., M.I.Q., A.T., A.H.D.), Imperial College London; and the Department of Non-communicable Disease Epidemiology (A.J.F.), London School of Hygiene and Tropical Medicine, UK.
authors.forename: Ankur
authors.initials: A
authors.lastname: Thapar
authors.affiliation: From the Academic Section of Vascular Surgery (A.B.M., M.I.Q., A.T., A.H.D.), Imperial College London; and the Department of Non-communicable Disease Epidemiology (A.J.F.), London School of Hygiene and Tropical Medicine, UK. a.h.davies@imperial.ac.uk.
authors.forename: Alun H
authors.initials: AH
authors.lastname: Davies
mesh_terms: D002423:Cause of Death / Q000639:trends*; D016208:Databases, Factual; D016894:Endarterectomy, Carotid / Q000009:adverse effects* / Q000401:mortality*; D006801:Humans; D015994:Incidence; D061214:Patient Safety / Q000706:statistics & numerical data*; D011183:Postoperative Complications / Q000453:epidemiology*; D012042:Registries; D020521:Stroke / Q000453:epidemiology*