The effects of a temperature below 15 degrees C on the myocardial calcium and ultrastructure in donor heart preservation in a canine model.
The effects of 6-h hypothermic cardioplegic arrest on myocardial biochemical, morphologic, and functional recovery were investigated in two groups of dogs. Group 1 (n = 6) was subjected to hypothermia of 15 degrees C and group 2 (n = 6) was subjected hypothermia of 5 degrees C. Although the myocardial calcium (Ca) concentration was significantly higher at the end of reperfusion in group 2 compared to group 1, the MB-fraction of creatine kinase, mitochondrial aspartate aminotransferase, recovery of left ventricular systolic function, and mitochondrial morphologic integrity were better in group 2 than in group 1. These findings suggest that hypothermia of 5 degrees C in 6-h cardioplegia is not necessarily coupled with interference in myocardial contractility, despite the Ca overload that occurs during reperfusion.
Sunamori
M
M
Department of Thoracic-Cardiovascular Surgery, Tokyo Medical and Dental University, School of Medicine, Japan.
Amano
J
J
Suzuki
A
A
D000818:Animals; D001219:Aspartate Aminotransferases / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D003402:Creatine Kinase / Q000378:metabolism; D004285:Dogs; D006321:Heart / Q000502:physiology; D006324:Heart Arrest, Induced / Q000379:methods*; D007036:Hypothermia, Induced; D007527:Isoenzymes; D008929:Mitochondria, Heart / Q000378:metabolism / Q000648:ultrastructure; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000378:metabolism* / Q000648:ultrastructure*; D009926:Organ Preservation / Q000379:methods*; D013696:Temperature; D013997:Time Factors; D014019:Tissue Donors; D016277:Ventricular Function, Left
D007527:Isoenzymes; D001219:Aspartate Aminotransferases; D003402:Creatine Kinase; D002118:Calcium