title: [Meta-analysis of percutaneous transluminal atherectomy in the treatment for in-stent restenosis of lower extremity peripheral artery disease].
abstract: OBJECTIVE
  To evaluate the clinical safety and efficacy of percutaneous transluminal atherectomy for in-stent restenosis (ISR) in patients with low extremity peripheral arterial diseases (PAD).
  
  
  METHODS
  PubMed, Elsevier, EBSCO, Spring databases and Cochrane Library were searched for relevant articles. Based on the different mechanisms of atherectomy, the patients were divided into mechanic atherectomy group and laser atherectomy group. The safety end points included the rate of distal embolism and severe arterial wall injuries. And the efficacy end points included primary patency rate and freedom from target vessel revascularization (TVR-free) 6 months and 12 months after surgery.
  
  
  RESULTS
  A total of 9 studies and 620 patients (published between 2006 and 2014) were accepted. The rate of distal embolism was 4.2% (95% confidence interval (CI): 1.7%-6.7%), while that of severe arterial wall injuries was 1.9% (95%CI: 0.9%-3.0%), respectively. Laser atherectomy was responsible for more distal embolism (6.8%) compared to mechanic atherectomy (2.0%), which was significantly different (Q=21.66, P=0.010). At 6-month follow-up, primary patency rate and rate of TVR-free were 63.0% (95% CI: 55.5%-70.6%) and 80.4% (95% CI: 70.5%-90.3%), while at 12-month follow-up were 43.5% (95%CI: 32.2%-54.9%) and 58.0% (95% CI: 52.1%-63.9%), respectively. The free-TVR rate at 6 months follow-up in mechanical atherectomy group was 77.9%, and was inferior to that in laser atherectomy group (80.8%, Q=13.49, P=0.009). Published bias was discovered at the analysis of 12-month TVR-free rate by means of Begg Test (P=0.039). Meta analysis concerned about the 3 randomized controlled trials demonstrated that there was no significant improvement using atherectomy for ISR comparing to standard balloon at 6-month TVR-free rate (OR=1.34, 95% CI: 0.86-2.07, P=0.196).
  
  
  CONCLUSIONS
  To treat ISR lesion in lower extremities, laser atherectomy has a lower free-TVR rate in the middle term follow-up.A higher rate of distal embolism is noted though. On balance, percutaneous transluminal atherectomy demonstrates no significant improvement compared to plain balloon angioplasty for ISR lesions.
authors.affiliation: Department of Vascular Surgery, Peking University People's Hospital, Beijing 100044, China.
authors.forename: Weihao
authors.initials: W
authors.lastname: Li
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: Liu
authors.forename: Yongbao
authors.initials: Y
authors.lastname: Zhang
authors.forename: Qingle
authors.initials: Q
authors.lastname: Li
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Email: scy@pkuph.edu.cn.
authors.forename: Chenyang
authors.initials: C
authors.lastname: Shen
mesh_terms: D000800:Angioplasty, Balloon; D015906:Angioplasty, Balloon, Coronary; D017073:Atherectomy; D003251:Constriction, Pathologic; D006801:Humans; D035002:Lower Extremity; D058729:Peripheral Arterial Disease; D015607:Stents