Metabolic enhancement of myocardial preservation during XXXX .

@entity1707 @entity1734 @entity2227 @entity8516 @entity6546 @entity4588 @entity26 @entity5910 @entity1167 @entity6564 @entity855
An experimental study was undertaken to evaluate the relative efficacy of oxygenated versus unoxygenated cardioplegic solutions and to determine if the addition of certain metabolically active substrates to cardioplegic solutions had any effect on myocardial preservation. Sixty-one @entity1707 were divided into seven groups of animals (5 to 15 animals per group). The impact of different cardioplegic vehicles, i.e., crystalloid versus the @entity26 -carrying vehicles, blood and Fluosol-DA, on preservation of high-energy @entity6546 ( @entity855 and @entity1734 ) was examined in the first three animal groups. The influence of Krebs cycle intermediates, i.e., @entity2227 , @entity5910 , @entity4588 and @entity8516 , on @entity855 and @entity1734 preservation was evaluated in the other four animal groups. All hearts underwent 120 minutes of hypothermic @entity1167 at 15 degrees C followed by 60 minutes of normothermic reperfusion. Higher @entity855 and @entity1734 levels were maintained during arrest when oxygenated solutions were used as the cardioplegic vehicle and when any of the four intermediates were added to the crystalloid cardioplegic solution, especially @entity4588 and fumarate. During reperfusion, however, @entity855 levels were uniformly lower than control whereas @entity1734 levels rose to either control levels or higher in all groups. No significant intergroup difference could be identified during reperfusion. These findings lead to the conclusion that the presence of either @entity26 or certain Krebs cycle intermediates enhances the protective effect of @entity6564 hypothermic cardioplegia on high-energy phosphates during the arrest period only. This enhancement is not maintained during the reperfusion period.
