title: Decreased incidence of low output syndrome with a switch from tepid to cold continuous minimally diluted blood cardioplegia in isolated coronary artery bypass grafting.
abstract: OBJECTIVE
  The optimal temperature for blood cardioplegia remains unclear.
  
  
  METHODS
  A retrospective analysis was performed on 138 patients undergoing isolated myocardial revascularization by a single surgeon in our institution over a period of 2 years. Patients operated on early in the study period received tepid (29°C) continuous minimally diluted blood cardioplegia (minicardioplegia), delivered in an antegrade continuous fashion. Later, our surgeon began using cold (7°C) blood minicardioplegia in all patients. Data pertaining to clinical outcomes and postoperative biochemical data were obtained, and the two groups were compared.
  
  
  RESULTS
  Low cardiac output syndrome, defined as the need for intra-aortic balloon pump counter pulsation or inotropic medication for haemodynamic instability, was more frequent in the tepid cardioplegia group than in the cold cardioplegia group (16.0 vs 2.4%, P = 0.006). There was no difference in the maximal serum creatine kinase MB between the two groups (cold 25.4 ± 3.21 μg/ml vs tepid 36.5 ± 7.10 μg/ml, P = 0.62), in the rates of perioperative myocardial infarction (cold 1.2% vs tepid 6.0%, P = 0.15) and the need for postoperative insertion of an intra-aortic balloon pump (cold 4.8% vs tepid 0.0%, P = 0.3). There was no other statistically significant difference between the two groups in the measured parameters.
  
  
  CONCLUSIONS
  A higher rate of low cardiac output syndrome in the tepid cardioplegia group suggests inferior myocardial protection with the tepid cardioplegia. Cold cardioplegia may provide better protection than tepid cardioplegia when minicardioplegia is used.
authors: Department of Cardiac Surgery,  Montreal Heart Institute, Université de Montréal, Montreal, Quebec,  Canada.
authors: Cristian
authors: C
authors: Rosu
authors: Maxime
authors: M
authors: Laflamme
authors: Clotilde
authors: C
authors: Perrault-Hébert
authors: Michel
authors: M
authors: Carrier
authors: Louis P
authors: LP
authors: Perrault
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D002303:Cardiac Output, Low / Q000453:epidemiology / Q000517:prevention & control*; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D003324:Coronary Artery Disease / Q000503:physiopathology / Q000601:surgery*; D052279:Creatine Kinase, MB Form / Q000097:blood; D005260:Female; D006324:Heart Arrest, Induced / Q000009:adverse effects / Q000379:methods*; D006439:Hemodynamics; D006801:Humans; D007036:Hypothermia, Induced / Q000009:adverse effects; D015994:Incidence; D007423:Intra-Aortic Balloon Pumping; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000453:epidemiology / Q000517:prevention & control; D011792:Quebec / Q000453:epidemiology; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D052279:Creatine Kinase, MB Form