Previously, we observed that reducing myocardial temperature in the risk region before @entity1563 caused a profound reduction in @entity1188 size. It is unknown whether lowering myocardial temperature after @entity63 has already begun, or just before reperfusion, is also effective in reducing @entity1188 size. This study tests the hypothesis that reducing myocardial temperature locally, after coronary occlusion, reduces @entity1188 size. METHODS: Anesthetized @entity95 received 30 min of @entity1563 and three hours of reperfusion. Myocardial temperature in the risk zone was monitored. @entity95 were randomly assigned to one of three groups: group 1, topical @entity296 starting 10 min after coronary occlusion (n = 11); group 2, cooling starting 25 min after coronary occlusion (n = 11); or group 3, control, no intervention (n = 10). RESULTS: Hemodynamic parameters and regional myocardial blood flow were equivalent in all groups. Risk zone temperature was similar in all groups at occlusion. The cooling maneuver produced a rapid reduction in temperature in the risk region. In group 1, myocardial temperature was reduced an average of 6.3 degrees C between 10 and 15 min of @entity1563 ; myocardial temperature in group 2 was reduced an average of 5.9 degrees C between 25 and 30 min of @entity1563 . Cooling was maintained until 15 min of reperfusion. Myocardial temperature in group 3 remained within 0.3 degree C of baseline during @entity1563 and into reperfusion. Core temperature was similar in all groups. Although the @entity63 risk region was comparable in all groups, early cooling (group 1) resulted in a significant reduction in @entity1188 size, expressed as a fraction of the risk region, compared with the control group (0.23 +/- 0.04 vs. 0.44 +/- 0.04 of the risk region); however, cooling just before reperfusion (group 2) failed to modify @entity1188 size compared with the controls (0.43 +/- 0.04 and 0.44 +/- 0.04 of the risk region, respectively). CONCLUSION: These results support our hypothesis that reducing myocardial temperature reduces @entity1188 size. However, it is important the reduction in temperature be produced as early as possible following @entity1563 .

Regional hypothermia reduces XXXX even when instituted after the onset of @entity63 .

@entity296 :: ('MESH:D009202', 'Disease') :: ['myocardial cooling'] @entity63 :: ('MESH:D007511', 'Disease') :: ['ischemia', 'ischemic'] @entity1563 :: ('MESH:D054059', 'Disease') :: ['coronary artery occlusion'] @entity95 :: ('9986', 'Species') :: ['Rabbits', 'rabbits'] @entity1188 :: ('MESH:D007238', 'Disease') :: ['infarct']
@entity296 :: (MESH:D009202,Disease) :: ['myocardial necrosis']
