BackgroundThe prognostic factors of in-hospital mortality in all comers and unselected patients with ST elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) have not been well established. Objective To identify the predictive factors of inhospital mortality in patients with STEMI undergoing primary PCI in a tertiary heart centre. Methods Between January 2008 and December 2011, all patients with STEMI undergoing primary PCI were retrospectively included in this study. Baseline characteristics and angiographic data were reviewed and recorded. The study endpoint was all-cause in-hospital mortality.Results Of the 541 patients included in the study, 63 (11.6%) died during hospitalisation. Cardiogenic shock at admission was recorded in 301 patients (55.6%) and 424 patients (78%) had multivessel disease. Median door-to-device time was 65 min. After adjustment for baseline variables, the factors associated with in-hospital mortality included age >60 years (OR 2.98, 95% CI 1.17 to 7.05; p=0.01), left ventricular ejection fraction <40% (OR 2.53, 95% CI 1.20 to 5.36; p=0.02), and final TIMI flow grade 0/1 (OR 20.55, 95% CI 3.49 to 120.94; p=0.001). Conclusions Age, left ventricular function and final TIMI flow are significant predictors of adverse outcomes in unselected patients with STEMI undergoing primary PCI.