title: Alternate antegrade/retrograde perfusion: an effective technique to preserve hypertrophied hearts during valvular surgery.
abstract: OBJECTIVE
  Continuous antegrade perfusion (AP) may interfere with surgical precision. Continuous retrograde perfusion (RP), on the other hand, cannot sustain the empty-beating hypertrophied hearts. Therefore, alternate antegrade/retrograde perfusion (A(A/R)P) may be a rational technique to preserve the hypertrophied hearts. This study is to determine whether A(A/R)P could maintain myocardial energy metabolism, oxygenation, and contractile function of the empty-beating hypertrophied hearts.
  
  
  METHODS
  Sixteen hypertrophied pig hearts were divided into four groups (n=4 per group). Group I and II underwent an 80-min A(A/R)P (four 10-min APs and four 10-min RPs), followed by a 20-min reperfusion. Group III and IV were subjected to an 80-min AP and 20-min reperfusion and used as a control. Energy metabolism was evaluated in group I and III using magnetic resonance spectroscopy. Myocardial oxygenation (MO) was assessed in group II and IV using near infrared spectroscopic imaging.
  
  
  RESULTS
  During 80-min A(A/R)P, four episodes of RP resulted in a significant decrease in myocardial phosphocreatine (PCr) and MO. The subsequent AP, however, resulted in complete recovery of the parameters. Moreover, myocardial adenosine triphosphate (ATP) remained at a normal level throughout the 80-min A(A/R)P. As expected, hearts in groups III and IV showed normal level of myocardial PCr, ATP, and MO throughout protocol. Finally, hearts in all four groups showed similar contractile function during reperfusion.
  
  
  CONCLUSIONS
  A(A/R)P with four 10-min intervals of AP and RP sustained normal myocardial energy metabolism, oxygenation, and contractile function of empty-beating hypertrophied hearts. We conclude that A(A/R)P is an effective technique for preservation of empty-beating hypertrophied hearts during valvular surgery.
authors.affiliation: Institute for Biodiagnostics, National Research Council, 435 Ellice Avenue, Winnipeg, Manitoba, Canada.
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Hongyu
authors.initials: H
authors.lastname: Liu
authors.forename: Tomas A
authors.initials: TA
authors.lastname: Salerno
authors.forename: Boguslaw
authors.initials: B
authors.lastname: Tomanek
authors.forename: Randy
authors.initials: R
authors.lastname: Summers
authors.forename: Roxanne
authors.initials: R
authors.lastname: Deslauriers
authors.forename: Rakesh C
authors.initials: RC
authors.lastname: Arora
authors.forename: Ganghong
authors.initials: G
authors.lastname: Tian
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004734:Energy Metabolism; D006349:Heart Valve Diseases / Q000150:complications / Q000503:physiopathology / Q000601:surgery; D006351:Heart Valves / Q000601:surgery*; D017379:Hypertrophy, Left Ventricular / Q000150:complications / Q000503:physiopathology*; D007430:Intraoperative Care / Q000379:methods; D009200:Myocardial Contraction; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000378:metabolism; D010101:Oxygen Consumption; D010477:Perfusion / Q000379:methods*; D034421:Sus scrofa