title: Systematic review and meta-analysis of additional technologies to enhance angioplasty for infrainguinal peripheral arterial occlusive disease.
abstract: BACKGROUND
  There are several additional techniques designed to enhance conventional percutaneous transluminal balloon angioplasty (PTA). This systematic review assessed current evidence on the clinical effectiveness of additional techniques for infrainguinal peripheral arterial occlusive disease (PAD).
  
  
  METHODS
  Relevant electronic databases, including MEDLINE, were searched in May 2011. The population comprised participants with symptomatic PAD undergoing endovascular treatment for disease distal to the inguinal ligament. Interventions were additional techniques compared with conventional PTA. Main outcome measures were restenosis and need for reintervention. Randomized clinical trials (RCTs) of clinical effectiveness were assessed for quality and data were extracted. Where appropriate, meta-analysis was undertaken to produce risk ratios (RRs).
  
  
  RESULTS
  Forty RCTs were selected. Meta-analysis showed a significant benefit in reducing restenosis rates at 6 months for self-expanding stents (RR 0.49) and drug-coated balloons (RR 0.40), and at 12 months for endovascular brachytherapy (RR 0.63). There was also evidence that use of a stent-graft significantly reduced restenosis compared with PTA, as did drug-eluting stents compared with bare-metal stents. Meta-analysis showed that use of drug-coated balloons was associated with significantly lower reintervention rates than PTA alone at 6 months (RR 0.24) and 24 months (RR 0.27) of follow-up. There was also evidence of significantly lower reintervention rates for self-expanding stents at 6 months. Other techniques did not show significant treatment effects for restenosis or reintervention.
  
  
  CONCLUSIONS
  The conclusions of this review should be tempered by small sample sizes, lack of clinical outcome measures and differing outcome definitions, making direct comparison across trials difficult. However, self-expanding stents, drug-eluting stents and drug-coated balloons appeared to be the most promising technologies worthy of future study.
authors.affiliation: School of Health and Related Research, University of Sheffield, Sheffield, UK. e.l.simpson@sheffield.ac.uk
authors.forename: E L
authors.initials: EL
authors.lastname: Simpson
authors.forename: J A
authors.initials: JA
authors.lastname: Michaels
authors.forename: S M
authors.initials: SM
authors.lastname: Thomas
authors.forename: A J
authors.initials: AJ
authors.lastname: Cantrell
mesh_terms: D000800:Angioplasty, Balloon / Q000379:methods*; D001157:Arterial Occlusive Diseases / Q000628:therapy*; D054855:Drug-Eluting Stents; D006801:Humans; D007264:Inguinal Canal / Q000098:blood supply; D016491:Peripheral Vascular Diseases / Q000628:therapy*; D016032:Randomized Controlled Trials as Topic; D012086:Reoperation; D055502:Secondary Prevention; D016896:Treatment Outcome