The Effect of Temperature of Cardioplegic Soultion on Myocardial Protection from Ischemia - Experimental Study using Isolated Rat Heart Perfusion Technique -

흰쥐의 적출된 심장에서 심정지액의 온도가 심근보호에 미치는 영향

The effect of temperature of cardioplegic solution on myocardial preservation was studied using isolated rat heart perfusion technique. Twenty Sprague-Dawley rats, weighing 120~140gm, were pretreated with intraperitoneal injection of heparin sodium[300u/kg] and then the hearts were excised after cervical herniation 30 minutes later. The hearts were perfused in isolated working heart apparatus with oxygenated modified Tyrode solution at 37oC. After 10 minutes of non working heart perfusion, the hearts were subjected to arrest for 30 minutes by administration of 5cc cardioplegic solution at the temperature of 4oC [Group I ], 15oC [Group II], 25oC [Group III], 37oC[Group IV]. At the same time, the topical cooling of heart was performed using ice saline. After arrest, the hearts were reperfused by non working heart perfusion for 1 hour with modified Tyrode solution at 37oC. The CPK, GOT and LDH in reperfusate were measured at 5,20,40,60 minutes after start of reperfusion. With the values of those, we compared the effect of temperature of cardioplegic solution on myocardial preservation. The results were as follows; 1. The enzyme values in reperfusate were highest at 5 minute and after then declined. 2. At 5 minutes after reperfusion, the enzyme values in Group I were lower than those in other Groups. These results suggest that the cardioplegic solutions using for cardiac arrest and myocardial protection can be working better at 4oC than at any other temperature.