Insulin(GIK) improves myocardial metabolism in patients during blood cardioplegia.
The aim of this study was to test the hypothesis that abnormalities of myocardial substrate metabolism during blood cardioplegic aortic cross-clamping and early reperfusion are attenuated further by insulin(GIK) than by alpha-ketoglutarate enrichment of blood cardioplegia alone. Twenty-eight males (47 to 78 years) undergoing coronary artery bypass grafting (CABG) participated in a prospective, controlled, randomized study. All patients had alpha-ketoglutarate-enriched blood cardioplegia. Insulin(GIK) was infused in 13 patients during aortic cross-clamping. Insulin(GIK) prevented lactate release during cardioplegia (1.5+/-15 vs -44+/-14 micromol/min, p = 0.04), and a significant extraction of lactate was induced shortly after declamping the aorta (15+/-3 vs 2+/-1%, p = 0.001). Free fatty acid uptake was reduced after cardioplegic cross-clamping (5.7+/-1.6 vs 16.0+/-3.8 micromol/min, p = 0.02). More positive/less negative levels of alanine, aspartate, glutamine, glycine, ornithine, taurine and tyrosine were found in all the insulin-treated patients. We conclude that insulin(GIK) attenuates abnormalities of myocardial substrate metabolism during blood cardioplegic aortic cross-clamping and early reperfusion further than is obtained with alpha-ketoglutarate enrichment of blood cardioplegia alone.
Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, Göteborg, Sweden.
U W
UW
Kjellman
K
K
Björk
A
A
Dahlin
R
R
Ekroth
K
K
Kirnö
G
G
Svensson
J
J
Wernerman
D000368:Aged; D000596:Amino Acids / Q000097:blood; D002314:Cardioplegic Solutions; D002952:Citric Acid Cycle / Q000187:drug effects / Q000502:physiology; D001026:Coronary Artery Bypass; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology; D005950:Glucose Solution, Hypertonic / Q000008:administration & dosage; D006801:Humans; D007036:Hypothermia, Induced; D007262:Infusions, Intravenous; D007328:Insulin / Q000008:administration & dosage*; D007333:Insulin Resistance / Q000502:physiology; D007656:Ketoglutaric Acids / Q000008:administration & dosage; D019344:Lactic Acid / Q000097:blood; D008875:Middle Aged; D015428:Myocardial Reperfusion Injury / Q000503:physiopathology / Q000517:prevention & control*; D009206:Myocardium / Q000378:metabolism*; D011188:Potassium / Q000008:administration & dosage; D011446:Prospective Studies
D000596:Amino Acids; D002314:Cardioplegic Solutions; D005950:Glucose Solution, Hypertonic; D007328:Insulin; D007656:Ketoglutaric Acids; D019344:Lactic Acid; D011188:Potassium