title: Outcome of infra-inguinal bypass grafts using vein conduit with less than 3 millimeters diameter in critical leg ischemia.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the difference in amputation-free survival and patency rates of infra-inguinal bypass grafts in patients with critical leg ischemia (CLI) with vein conduits with an internal diameter <3 mm compared to those with vein conduits with a diameter of ≥ 3 mm.
  
  
  METHODS
  Retrospective analysis of all consecutive patients with CLI undergoing infra-inguinal bypass. Preoperative duplex scan mapping and measurement of potential vein grafts were performed on all patients. Patients were recruited in a 1-year duplex scan graft surveillance program. Primary end points were amputation-free survival and patency rates at 1 year postoperatively. Kaplan-Meier and χ(2) test were used for statistical analysis.
  
  
  RESULTS
  Between January 2004 and April 2010, 157 consecutive patients with CLI underwent 171 bypasses using vein conduits (111 men, 46 women; median age, 75 years; range, 45-96 years). Ninety-three bypasses (54.4%) were performed for tissue loss, 44 (25.7%) for gangrene, and for rest pain. Of the 157 patients, 113 (72.0%) had diabetes mellitus, 40 (25.5%) had renal impairment, 131 (83.4%) had hypertension, and 64 (40.8%) had ischemic heart disease. Femoro-popliteal bypass was performed in 38 cases (22.2%), whereas 133 (77.8%) of the bypasses were femoro-distal. Autogenous great saphenous vein (GSV) was used in all cases. All grafts were reversed. The diameter of 31 (18%) vein conduits measured <3 mm (range, 2-2.9 mm) on preoperative duplex scan. One hundred thirty-four grafts had at least 1-year follow-up. The primary, assisted primary, and secondary patency rates at 1 year for vein conduits <3 mm were 51.2%, 82.6%, and 82.6%, respectively, compared to 68.4%, 93.3%, and 95.2%, respectively, in the ≥ 3 mm group. This was only significant for the secondary patency (P = .0392). The amputation-free survival at 48 months was 70.8% for vein conduits <3 mm and 57.3 for vein conduits ≥ 3 mm.
  
  
  CONCLUSIONS
  This series has shown that primary and assisted primary patency rates in small veins are not significantly different at 1 year but the secondary patency rates are better in the larger veins. Similarly, the amputation-free survival was also comparable. The authors would, therefore, advocate the use of small veins >2 mm in diameter in patients with CLI. Duplex scan surveillance followed by early salvage angioplasty for threatened grafts is needed to achieve good patency rates in both groups.
authors.affiliation: Department of Vascular Surgery, King’s College Hospital, London SE5 9RS, United Kingdom. hisham.rashid@nhs.net
authors.forename: Hani
authors.initials: H
authors.lastname: Slim
authors.forename: Alok
authors.initials: A
authors.lastname: Tiwari
authors.forename: Jens Carsten
authors.initials: JC
authors.lastname: Ritter
authors.forename: Hisham
authors.initials: H
authors.lastname: Rashid
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000671:Amputation, Surgical; D016009:Chi-Square Distribution; D016638:Critical Illness; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007511:Ischemia / Q000000981:diagnostic imaging / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D053208:Kaplan-Meier Estimate; D008131:London; D035002:Lower Extremity / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D012086:Reoperation; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012501:Saphenous Vein / Q000000981:diagnostic imaging / Q000637:transplantation*; D013997:Time Factors; D016896:Treatment Outcome; D018616:Ultrasonography, Doppler, Duplex; D058017:Vascular Grafting / Q000009:adverse effects / Q000401:mortality; D014654:Vascular Patency