title: Alternative conduit for infrageniculate bypass in patients with critical limb ischemia.
abstract: BACKGROUND
  Autologous great saphenous vein (GSV) has always been considered the gold standard conduit for infrainguinal revascularization. When GSV is inadequate or unavailable, alternative conduits have been used. In this study, we compared modern outcomes of different conduit types used in lower extremity bypass (LEB) for patients with critical limb ischemia (CLI).
  
  
  METHODS
  The Vascular Study Group of New England database (2003-2014) was queried for patients who underwent infrageniculate bypass originating from the femoral arteries. Conduit types were categorized as single-segment GSV, alternative autologous conduit (AAC), and nonautologous conduit (NAC). Primary outcomes were 1-year freedom from major adverse limb event (MALE), MALE-free survival, and primary graft patency. Multivariable Cox regression was used to adjust for demographics and comorbidities.
  
  
  RESULTS
  LEB was performed in 2148 patients, of which 1125 were to below-knee popliteal (BK-Pop) and 1023 to infrapopliteal artery (IPA) targets. The baseline characteristics differed among the conduit groups: Patients in the GSV group were younger and had fewer comorbidities than in the AAC groups. Patients undergoing BK-Pop bypass with NAC had higher rates of postoperative myocardial infarction (7.1%) and postoperative (5.8%) and 1-year death (40.8%) than in those with GSV (3.1%, 2%, and 31.7%, respectively) and AAC (0%, 0%, and 25%, respectively). In multivariable analysis, conduit type did not make a difference in 1-year MALE, MALE-free survival, or primary graft patency for BK-Pop bypasses. For IPA bypasses, NAC use was associated with higher rates of postoperative (6.4%) and in-hospital death (4.5%) compared with GSV (2.5% and 1.4%, respectively) and AAC (2.9% and 1.9%, respectively). In adjusted analysis, NAC was associated with higher risk of MALE (hazard ratio [HR], 1.50; 95% confidence interval [CI], 1.03-2.20; P = .036) and primary patency loss (HR, 1.3; 95% CI, 0.91-1.89), and lower MALE-free survival (HR, 1.47; 95% CI, 1.03-2.09; P = .035) compared with GSV. There was no difference between the NAC and AAC groups.
  
  
  CONCLUSIONS
  Conduit type does not affect outcomes in BK-Pop bypass. In the absence of single-segment GSV, the use of AAC for IPA bypass does not appear to confer any additional benefit of MALE, MALE-free survival, or graft patency compared with prosthetic grafts at 1-year follow-up.
authors.affiliation: Division of Vascular Surgery, Rhode Island Hospital, Warren Alpert School of Medicine, Brown University, Providence, RI. Electronic address: carla_moreira@brown.edu.
authors.forename: Carla C
authors.initials: CC
authors.lastname: Moreira
authors.affiliation: Division of Vascular and Endovascular Surgery, Boston University School of Medicine and Boston Medical Center, Boston, Mass.
authors.forename: Alexander D
authors.initials: AD
authors.lastname: Leung
authors.affiliation: Division of Vascular and Endovascular Surgery, Boston University School of Medicine and Boston Medical Center, Boston, Mass.
authors.forename: Alik
authors.initials: A
authors.lastname: Farber
authors.affiliation: Department of Biostatistics, Boston University School of Medicine, Boston, Mass.
authors.forename: Denis
authors.initials: D
authors.lastname: Rybin
authors.affiliation: Department of Biostatistics, Boston University School of Medicine, Boston, Mass.
authors.forename: Gheorghe
authors.initials: G
authors.lastname: Doros
authors.affiliation: Division of Vascular and Endovascular Surgery, Boston University School of Medicine and Boston Medical Center, Boston, Mass.
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Siracuse
authors.affiliation: Division of Vascular and Endovascular Surgery, Boston University School of Medicine and Boston Medical Center, Boston, Mass.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Kalish
authors.affiliation: Division of Vascular and Endovascular Surgery, Boston University School of Medicine and Boston Medical Center, Boston, Mass.
authors.forename: Mohammad H
authors.initials: MH
authors.lastname: Eslami
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D064591:Allografts; D064592:Autografts; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D016009:Chi-Square Distribution; D016638:Critical Illness; D016208:Databases, Factual; D018572:Disease-Free Survival; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007511:Ischemia / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D053208:Kaplan-Meier Estimate; D035002:Lower Extremity / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009511:New England; D058729:Peripheral Arterial Disease / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D011150:Popliteal Artery / Q000503:physiopathology / Q000601:surgery*; D011183:Postoperative Complications / Q000209:etiology / Q000401:mortality; D016016:Proportional Hazards Models; D011474:Prosthesis Design; D012189:Retrospective Studies; D012307:Risk Factors; D012501:Saphenous Vein / Q000503:physiopathology / Q000637:transplantation*; D013997:Time Factors; D016896:Treatment Outcome; D014654:Vascular Patency