title: The anastomosis angle is a key to improved long-term patency of proximal femoropopliteal bypass.
abstract: BACKGROUND
  Femoropopliteal bypass is a common vascular reconstructive procedure. A significant proportion of bypasses become ineffective within 1 year because of occlusion due to progression of intimal hyperplasia (IH).
  
  
  METHODS
  The clinical part of the study involved an analysis of 43 patients with proximal femoropopliteal bypass, which became occluded no later than 1 year from the procedure, who were successfully treated with thrombolysis. Morphological changes of intima in the anastomosis (evaluated angiographically) and the angle of the distal end-to-side anastomosis were evaluated. In the second part of the study, blood flow in the distal end-to-side anastomosis was modeled experimentally (by particle image velocimetry) and numerically (by computational fluid dynamics). The results were correlated with the previously identified locations of IH.
  
  
  RESULTS
  We proved that the locations of IH correlate with the locations of disturbed blood flow, increased wall shear stress, and stagnation points as documented by experimental visualization and angiographic findings. We also confirmed that anastomoses with more acute angles are less prone to IH and occlusion of the lumen.
  
  
  CONCLUSIONS
  We suggest that a better understanding of the hemodynamics and its influence on IH should lead to an optimized graft design by adopting a more acute angle of the anastomosis.
authors.affiliation: Department of Cardiovascular Surgery, General University Hospital, Prague, Czech Republic.
authors.forename: T
authors.initials: T
authors.lastname: Grus
authors.forename: J
authors.initials: J
authors.lastname: Lindner
authors.forename: T
authors.initials: T
authors.lastname: Vidim
authors.forename: J
authors.initials: J
authors.lastname: Tosovsky
authors.forename: J
authors.initials: J
authors.lastname: Matecha
authors.forename: V
authors.initials: V
authors.lastname: Rohn
authors.forename: L
authors.initials: L
authors.lastname: Lambert
authors.forename: G
authors.initials: G
authors.lastname: Grusova
mesh_terms: D000714:Anastomosis, Surgical; D001157:Arterial Occlusive Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D003198:Computer Simulation; D005263:Femoral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000209:etiology* / Q000503:physiopathology; D006439:Hemodynamics; D006801:Humans; D006965:Hyperplasia; D008955:Models, Cardiovascular; D011150:Popliteal Artery / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D011859:Radiography; D012008:Recurrence; D013314:Stress, Mechanical; D015912:Thrombolytic Therapy; D013997:Time Factors; D016896:Treatment Outcome; D017539:Tunica Intima / Q000000981:diagnostic imaging; D014654:Vascular Patency; D014656:Vascular Surgical Procedures / Q000009:adverse effects* / Q000379:methods