Blood cardioplegia with N-acetylcysteine may reduce coronary endothelial activation and myocardial oxidative stress.
OBJECTIVE
The aim of this prospective study was to compare the efficacy of intermittent antegrade blood cardioplegia with or without n-acetylcysteine (NAC) in reducing myocardial oxidative stress and coronary endothelial activation.


METHODS
Twenty patients undergoing elective isolated coronary artery bypass graft surgery were randomly assigned to receive intermittent antegrade blood cardioplegia (32 degrees C-34 degrees C) with (NAC group) or without (control group) 300 mg of NAC. For these 2 groups we compared clinical outcome, hemodynamic evolution, systemic plasmatic levels of troponin I, and plasma concentrations of malondialdehyde (MDA) and soluble vascular adhesion molecule 1 (sVCAM-1) from coronary sinus blood samples.


RESULTS
Patient demographic characteristics and operative and postoperative data findings in both groups were similar. There was no hospital mortality. Comparing the plasma levels of MDA 10 min after the aortic cross-clamping and of sVCAM-1 30 min after the aortic cross-clamping period with the levels obtained before the aortic clamping period, we observed increases of both markers, but the increase was significant only in the control group (P= .039 and P= .064 for MDA; P= .004 and P= .064 for sVCAM-1). In both groups there was a significant increase of the systemic serum levels of troponin I compared with the levels observed before cardiopulmonary bypass (P< .001), but the differences between the groups were not significant (P= .570).


CONCLUSIONS
Our investigation showed that NAC as an additive to blood cardioplegia in patients undergoing on-pump coronary artery bypass graft surgery may reduce oxidative stress and the resultant coronary endothelial activation.
Rodrigues
Alfredo J
AJ
Faculty of Medicine of Ribeirão Preto of the University of São Paulo, Department of Surgery and Anatomy, São Paulo, Brazil. alfredo@fmrp.usp.br
Evora
Paulo R B
PR
Bassetto
Solange
S
Alves
Lafaiete
L
Scorzoni Filho
Adilson
A
Origuela
Eliana A
EA
Vicente
Walter V A
WV
D000111:Acetylcysteine / Q000008:administration & dosage*; D003131:Combined Modality Therapy; D003324:Coronary Artery Disease / Q000628:therapy*; D004730:Endothelium, Vascular / Q000187:drug effects; D005260:Female; D016166:Free Radical Scavengers / Q000008:administration & dosage; D006324:Heart Arrest, Induced / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects; D016896:Treatment Outcome; D014661:Vasoconstriction / Q000187:drug effects
D016166:Free Radical Scavengers; D000111:Acetylcysteine