DEFEROXAMINE CARDIOPLEGIA REDUCES SUPEROXIDE RADICAL PRODUCTION IN HUMAN MYOCARDIUM

Recent studies have demonstrated enhanced myocardial protection during ischemia using the oxygen free radical scavenger, deferoxamine. This effect of deferoxamine may be related either to its iron-chelating property or to intervention in an iron-independent mechanism. We tested the latter by determining the rate of superoxide anion production and the degree of lipid peroxidation in human myocardial tissue after including deferoxamine in cardioplegic solution. Fourteen patients who underwent aortic, mitral, or double valve replacement were included in the study. The mean value for superoxide radical production was 59.8 +/- 17.0 nmol.min(-1).g(-1) for the control group (group C; n = 7) and 21.3 +/- 8.1 (p < 0.001) for the deferoxamine-treated group (group D; n = 7). The mean value for thiobarbituric reactive substances was 80.00 +/- 23.4 in group C and 38.7 +/- 23.8 nmol.min(-1).g(-1) in group D (p < 0.01). In conclusion, deferoxamine appears to have a moderating effect on the biochemical markers of ischemia reperfusion injury. Its scavenging effect on superoxide anion could play a role in the cellular defense against oxygen radicals during cardiac operations.