Percutaneous coronary interventions (PCIs) within a door-to-balloon timing of 90 min have greatly decreased mortality and morbidity of ST-elevation myocardial infarction (STEMI) patients. Post-PCI, they are routinely transferred into the coronary care unit (CCU) regardless of the severity of their condition, resulting in frequent CCU overcrowding. This study assesses the feasibility of step-down units (SDUs) as an alternative to CCUs in the management of STEMI patients after successful PCI, to alleviate CCU overcrowding. Criteria of assessment include in-hospital complications, length of stay, cost-effectiveness, and patient outcomes up to a year after discharge from hospital. A retrospective case-control study was done using data of 294 adult STEMI patients admitted to the emergency departments of two training and research hospitals and successfully underwent primary PCI from 1 January 2014 to 31 December 2015. Patients were followed up for a year post-discharge. Student t test and χ2 test were done as univariate analysis to check for statistical significance of p