Reperfusion therapy reduces mortality in patients presenting with ST-segment elevation myocardial infarctions (STEMI). However, some patients may not receive thrombolytic therapy or undergo primary percutaneous coronary intervention. The decision making and clinical outcomes of these patients have not been well described. In this study, 139 patients were identified from a total of 1,126 patients with STEMI who did not undergo reperfusion therapy at a high-volume percutaneous coronary intervention center from October 2006 to March 2011. Clinical data, reasons for no reperfusion, management, and mortality were obtained by chart review. The mean age was 80 ± 13 years (61% women, 31% diabetic, and 37% known coronary artery disease). Of the 139 patients, 72 (52%) presented with primary diagnoses other than STEMI, and 39 (28%) developed STEMI >24 hours after admission. The most common reasons for no reperfusion were advanced age, co-morbid conditions, acute or chronic kidney injury, delayed presentation, advance directives precluding reperfusion, patient preference, and dementia. Eighty-four patients (60%) had ≥3 reasons for no reperfusion. Factors associated with hospital mortality were cardiogenic shock, intubation, and advance directives prohibiting reperfusion after physician consultation. In hospital and 1-year mortality were 53% and 69%, respectively. In conclusion, at a high-volume percutaneous coronary intervention center, most patients presenting with STEMI underwent immediate catheterization. The decision for no reperfusion was multifactorial, with advanced age reported as the most common factor. Outcomes were poor in this population, and fewer than half of these patients survived to hospital discharge.