title: The impact of sequential versus single anastomoses on flow characteristics and mid-term patency of saphenous vein grafts in coronary bypass grafting.
abstract: OBJECTIVE
  To assess the influence of bypass grafting technique on the flow characteristics and mid-term patency of saphenous vein coronary bypass grafts.
  
  
  METHODS
  In the present study, 309 patients who underwent either sequential (group A, N = 84 grafts) or individual (group B, N = 244 grafts) saphenous vein coronary bypass grafting between February 2002 and September 2007 were investigated. Individual bypassing only was performed in 212 patients, and sequential bypassing only was performed in 78 patients. The remaining 19 patients received both. A total of 436 distal anastomoses were performed with 328 saphenous vein grafts. The intraoperative flow characteristics and the graft patency were assessed with the transit time flow meter and serial multi-detector computed tomography coronary angiograms, respectively.
  
  
  RESULTS
  Group A showed a higher mean flow compared with group B at 49.4 ± 27.4 mL/min versus 37.1 ± 20.1 mL/min, respectively (P = .001). The mean flow increased linearly as the number of anastomoses increased per graft (P < .001). Graft patency at 3 years was 93.3% ± 3.4% in group A and 86.5% ± 3.1% in group B (P = .048). After adjustment for baseline characteristics, group A showed a tendency for superior mid-term patency than group B (hazard ratio 0.362; 95% confidence interval, 0.129-1.017; P = .0538).
  
  
  CONCLUSIONS
  Sequential bypass grafts were associated with higher mean flows and superior mid-term patency compared with individual grafts. These findings suggest the more favorable results of sequential bypass grafting to be attributed to the enhanced flow hemodynamics.
authors.affiliation: Department of Cardiovascular Surgery, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea.
authors.forename: Hee Jung
authors.initials: HJ
authors.lastname: Kim
authors.forename: Taek Yeon
authors.initials: TY
authors.lastname: Lee
authors.forename: Joon Bum
authors.initials: JB
authors.lastname: Kim
authors.forename: Won Chul
authors.initials: WC
authors.lastname: Cho
authors.forename: Sung Ho
authors.initials: SH
authors.lastname: Jung
authors.forename: Cheol Hyun
authors.initials: CH
authors.lastname: Chung
authors.forename: Jae Won
authors.initials: JW
authors.lastname: Lee
authors.forename: Suk Jung
authors.initials: SJ
authors.lastname: Choo
mesh_terms: D000368:Aged; D016009:Chi-Square Distribution; D017023:Coronary Angiography / Q000379:methods; D001026:Coronary Artery Bypass / Q000009:adverse effects / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D003326:Coronary Circulation; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D056910:Republic of Korea; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012501:Saphenous Vein / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000637:transplantation*; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014654:Vascular Patency