Figure 4.

Continuous registration of the temperatures in the coronary arterial blood, the proximal infarct area, the mid infarct area, the distal infarct area, and the reference myocardium during one experiment. After the coronary artery is occluded, there is a rapid induction of the target temperature in the infarcted myocardium during an infusion of 30 ml/min saline at 22°C. The temperature remains stable during the occlusion phase. In the reperfusion phase (middle vertical line), the infusion rate is maintained at 30 ml/min, but the temperature is lowered to 4°C. This results in a stable myocardial temperature in the infarct area. In the reperfusion phase, the temperatures at the different sites within the infarct area are closer to the temperature in the coronary artery. This is explained in the discussion. During the very short time needed to change the temperature of the infused saline (between the left and middle vertical line), only coronary temperature increases rapidly, but myocardial temperature remains at the target temperature. Temperatures normalize rapidly after stopping saline infusion during the reperfusion phase (right vertical line).