This study investigated whether postconditioning during coronary angioplasty can protect the human heart during acute myocardial infarction (AMI). Thirty patients undergoing coronary angioplasty for ongoing AMI were randomly assigned to either a control or postconditioning group. Postconditioning involved four episodes of 1-minute inflation and 1-minute deflation of the angioplasty balloon within 1 minute of reflow. Infarct size was assessed by measuring total creatine kinase (CK) release over 72 hours. The area at risk and collateral blood flow were estimated using left ventricular and coronary angiograms. No adverse events occurred in the postconditioning group. Infarct size was significantly reduced in the postconditioning group compared to the control group, with a 36% reduction in infarct size. Blush grade, a marker of myocardial reperfusion, was significantly higher in the postconditioning group. The study suggests that postconditioning by coronary angioplasty protects the human heart during acute myocardial infarction. Postconditioning involves brief episodes of ischemia-reperfusion performed just after a prolonged ischemic insult and has been shown to reduce infarct size in experimental models. Unlike ischemic preconditioning, postconditioning can be applied in clinical practice during PTCA. The study found that postconditioning reduced infarct size and improved myocardial reperfusion. The results suggest that postconditioning is a feasible, safe, and efficient cardioprotective intervention that may reduce infarct size and improve outcomes in patients with AMI. Further studies are needed to confirm the long-term benefits of postconditioning.This study investigated whether postconditioning during coronary angioplasty can protect the human heart during acute myocardial infarction (AMI). Thirty patients undergoing coronary angioplasty for ongoing AMI were randomly assigned to either a control or postconditioning group. Postconditioning involved four episodes of 1-minute inflation and 1-minute deflation of the angioplasty balloon within 1 minute of reflow. Infarct size was assessed by measuring total creatine kinase (CK) release over 72 hours. The area at risk and collateral blood flow were estimated using left ventricular and coronary angiograms. No adverse events occurred in the postconditioning group. Infarct size was significantly reduced in the postconditioning group compared to the control group, with a 36% reduction in infarct size. Blush grade, a marker of myocardial reperfusion, was significantly higher in the postconditioning group. The study suggests that postconditioning by coronary angioplasty protects the human heart during acute myocardial infarction. Postconditioning involves brief episodes of ischemia-reperfusion performed just after a prolonged ischemic insult and has been shown to reduce infarct size in experimental models. Unlike ischemic preconditioning, postconditioning can be applied in clinical practice during PTCA. The study found that postconditioning reduced infarct size and improved myocardial reperfusion. The results suggest that postconditioning is a feasible, safe, and efficient cardioprotective intervention that may reduce infarct size and improve outcomes in patients with AMI. Further studies are needed to confirm the long-term benefits of postconditioning.