To evaluate the effects of pulsatile reperfusion (PR) on the postischemic myocardial phosphometabolites, 17 sheep were put on cardiopulmonary bypass (CPB) and randomly divided into a pulsatile group (P group) and nonpulsatile group (NP group). The heart was arrested by global ischemia for 45 minutes, then defibrillated and reperfused for 2 hours while the circulation was supported by CPB. Myocardial needle biopsies were obtained, and ATP, ADP, and AMP were measured with high performance liquid chromatography. There were no significant differences between the two groups in myocardial ADP and AMP. However, after 120 minutes of reperfusion, the myocardial ATP was restored in the P group, but continued to decrease further in the NP group. Experimental results imply that PR might reduce reperfusion injury and promote recovery of the ischemic myocardium.