title: Myocardial cooling with ice-slush provides no cardioprotective effects in aortic valve replacement.
abstract: OBJECTIVE
  Topical cooling of the heart with ice-slush has been widely used for myocardial protection. No prospective, randomized study has evaluated the effect of ice-slush on acknowledged markers (CK-MB, troponin-T) of myocardial damage during aortic valve replacement (AVR). This was the first aim of the present study. A second aim was to examine whether performing a study per se reduced myocardial damage.
  
  
  METHODS
  Sixty patients undergoing AVR were receiving cold crystalloid antegrade cardioplegia every 20 min. Thirty patients were randomized to achieve additional topical cooling with ice-slush. CK-MB and troponin-T were compared between groups as well as to a group of patients undergoing AVR immediately prior to the study.
  
  
  RESULTS
  There were no significant differences in myocardial markers between patients with or without ice-slush. However, we found significantly higher levels of troponin-T and CK-MB in patients undergoing AVR prior to start of the study.
  
  
  CONCLUSIONS
  Topical cooling with ice-slush does not provide additional cardioprotective effects. Comparison with an historical cohort indicates that administration of crystalloid cardioplegia following a rigid protocol might reduce myocardial damage.
authors.affiliation: Department of Cardiothoracic Surgery, Ullevål University Hospital, Oslo, Norway.
authors.forename: Bjørn
authors.initials: B
authors.lastname: Braathen
authors.forename: Oystein A
authors.initials: OA
authors.lastname: Vengen
authors.forename: Theis
authors.initials: T
authors.lastname: Tønnessen
mesh_terms: D000368:Aged; D001024:Aortic Valve Stenosis / Q000601:surgery*; D002314:Cardioplegic Solutions; D052279:Creatine Kinase, MB Form / Q000097:blood; D005260:Female; D006324:Heart Arrest, Induced / Q000379:methods*; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods*; D007053:Ice; D008297:Male; D008875:Middle Aged; D015428:Myocardial Reperfusion Injury / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D011184:Postoperative Period; D017680:Potassium Compounds; D011446:Prospective Studies; D013997:Time Factors; D020107:Troponin T / Q000097:blood
chemical_list: D002314:Cardioplegic Solutions; D007053:Ice; D017680:Potassium Compounds; D020107:Troponin T; C018369:potassium cardioplegic solution; D052279:Creatine Kinase, MB Form