Background: Coronary artery disease (CAD) and acute myocardial infarction are major causes of death and morbidity worldwide. This study aimed to assess short term clinical outcome in a patient of STEMI after primary PCI by using of APS. Methods: This prospective observational study included 100 patients with ST elevation myocardial infarction (STEMI) and underwent primary PCI within 12 h from symptom onset or between 12 and 24 h with evidence of continuing ischemia. Results: Death occurred in 7 (24.14%) patients in Failed Perfusion group, in 1 (1.49%) patient in Partial perfusion group and in 0 (0%) patients in Full perfusion. Re MI occurred in 5 (16.67%) patients in Failed Perfusion group, in 2 (2.94%) patients in Partial perfusion group and in 0 (0%) patients in Full perfusion. TVR occurred in 6 (20%) patients in Failed Perfusion group, in 2 (2.94%) patients in Partial perfusion group and in 1 (25%) patient in Full perfusion. The composite occurred in 9 (31.03%) patients in Failed Perfusion group, in 1 (1.49%) patient in Partial perfusion group and in 1 (25%) patient in Full perfusion. MACE (death, Re MI, TVR and composite) were significantly different among the three APS groups. mechanical complications were present in 4 (4%) patients. MACE was present in 35 (35%) patients. Regarding MACE, Death occurred in 8 (8%) patients, Re MI in 7 (7%) patients, TVR in 9 (9%) patients and Composite in 11 (11%) patients. Conclusion: The assessment of angiographic perfusion using the APS revealed significant associations with short-term clinical