Über die protektive Wirkung der Magnesium-Aspartat-Procain-Kardioplegie auf den hypertrophierten linken Ventrikel des Mini-Pigs

Abstract

After induction of left ventricular hypertrophy by supravalvar constriction of the ascending aorta in mini pigs (ATP and lactate) were measured under different cardioplegic conditions. In normothermia and plain anoxic arrest ATP decrease and lactate increase were significantly slower in hypertrophied myocardium compared to normal myocardium. Injection cardioplegia using magnesium-aspartate-procaine at 37 degrees C did not influence the ATP decrease and lactate increase in the hypertrophied ventricle, whereas in the normal heart it showed some protection according to these parameters. Optimal ATP preservation and the lowest lactate increase rate were achieved in left ventricular hypertrophy by combined application of magnesium-aspartate-procaine and hypothermia of 25 degrees C. We conclude that normothermic injection cardioplegia has no protective effect on the hypertrophied left ventricle, whereas additional hypothermia can improve magnesium-aspartate-procaine cardioplegia significantly.

Ultrastructural and Biochemical Changes of Human Papillary Heart Muscle during Different Methods of Induced Cardiac Arrest

“…MAP had no significant effect on myocardial ener gy demand in normothermia, it decreased the de cay rate of ATP significantly under similar condi tions of hypothermic cardiac arrest (10).…”

“…Engedal (6), applying profound topical myocardial hypothermia, and Fischer (7), combining myocar dial hypothermia with potassium-induced cardiac arrest, reported similar results. Considering the fact that cooling the heart is a common feature in all the cardioplegic methods described above, it appears that their main principle is homogeneous hypother mia of the myocardium (5,10).…”