title: Intraoperative Analysis of Flow Dynamics in Arteriovenous Composite Y Grafts.
abstract: Composite graft of left internal thoracic artery and great saphenous vein in revascularization of the left coronary system is a technique well described in literature. The aim of this study is to analyze blood flow dynamics in this configuration of composite graft especially in what concerns left internal thoracic artery's adaptability and influence of great saphenous vein segment on left internal thoracic artery's flow.
  
  
  
  Revascularization of left coronary system with composite graft, with left internal thoracic artery revascularizing the anterior interventricular artery and a great saphenous vein segment, anastomosed to the left internal thoracic artery, revascularizing another branch of the left coronary system, was performed in 23 patients. Blood flow was evaluated by transit time flowmetry in all segments of the composite graft (left internal thoracic artery proximal segment, left internal thoracic artery distal segment and great saphenous vein segment). Measures were performed in baseline condition and after dobutamine-induced stress, without and with non-traumatic temporary clamping of the distal segments of the composite graft.
  
  
  
  Pharmacological stress resulted in increase of blood flow values in the analyzed segments (P<0.05). Non-traumatic temporary clamping of great saphenous vein segment did not result in statistically significant changes in the flow of left internal thoracic artery distal segment, both in baseline condition and under pharmacological stress. Similarly, non-traumatic temporary clamping of left internal thoracic artery distal segment did not result in statistically significant changes in great saphenous vein segment flow.
  
  
  
  Composite grafts with left internal thoracic artery and great saphenous vein for revascularization of left coronary system, resulted in blood flow dynamics with physiological adaptability, both at rest and after pharmacological stress, according to demand. Presence of great saphenous vein segment did not alter physiological blood flow dynamics in distal segment of left internal thoracic artery.
authors.affiliation: Universidade Federal do Ceará (UFC), Fortaleza, CE, Brazil; Hospital de Messejana Dr. Carlos Alberto Studart Gomes, Fortaleza, CE, Brazil.
authors.forename: Heraldo Guedis
authors.initials: HG
authors.lastname: Lobo
authors.affiliation: Department of Surgery, Universidade Federal do Ceará (UFC), Fortaleza, CE, Brazil.
authors.forename: José Glauco
authors.initials: JG
authors.lastname: Lobo
authors.affiliation: Universidade Federal do Ceará (UFC), Fortaleza, CE, Brazil.
authors.forename: Matheus Duarte
authors.initials: MD
authors.lastname: Pimentel
authors.affiliation: Universidade Federal do Ceará (UFC), Fortaleza, CE, Brazil.
authors.forename: Bruno Gadelha Bezerra
authors.initials: BG
authors.lastname: Silva
authors.affiliation: Universidade Federal do Ceará (UFC), Fortaleza, CE, Brazil.
authors.forename: Camylla Santos
authors.initials: CS
authors.lastname: de Souza
authors.affiliation: Christus College, Fortaleza, CE, Brazil.
authors.forename: Marília Leitão
authors.initials: ML
authors.lastname: Montenegro
authors.affiliation: Christus College, Fortaleza, CE, Brazil.
authors.forename: Maria Cláudia de Azevedo
authors.initials: MC
authors.lastname: Leitão
authors.affiliation: Center for Research and Development of Medicines of Universidade Federal do Ceará(UFC), Fortaleza, CE, Brazil.
authors.forename: Francisco Vagnaldo Fechine
authors.initials: FV
authors.lastname: Jamacuru
mesh_terms: D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology*; D001026:Coronary Artery Bypass / Q000379:methods*; D005260:Female; D053805:Fractional Flow Reserve, Myocardial / Q000502:physiology*; D006801:Humans; D007387:Internal Mammary-Coronary Artery Anastomosis; D007432:Intraoperative Period; D008297:Male; D008323:Mammary Arteries / Q000502:physiology*; D008875:Middle Aged; D011446:Prospective Studies; D012501:Saphenous Vein / Q000502:physiology*; D058017:Vascular Grafting; D014654:Vascular Patency / Q000502:physiology; D014655:Vascular Resistance / Q000502:physiology