Aims: Age is one of the most powerful determinants of prognosis in myocardial infarction, but there is comparatively little recent data across the whole spectrum of acute coronary syndromes(ACS). We examined the impact of increasing age on clinical presentation and hospital outcome in a large sample of patients with ACS. Methods and results: Patients(n=10 253) from the Euroheart ACS survey in 103 hospitals in 25 countries were investigated. There was a significant inverse association between the age and the likelihood of presenting with ST-elevation. For each decade of life, the odds of presenting with ST-elevation decreased by 0.82 [95% confidence interval(CI) 0.79-0.84];P< 0.0001. Elderly patients were considerably less often treated by cardiologists, less extensively investigated, and, when presenting with ST-elevation ACS, less likely to be treated with reperfusion. Compared with patients< 55 years, the odds ratios of hospital mortality were 1.87(1.21-2.88) at age 55-64, 3.70(2.51-5.44) at age 65-74, 6.23(4.25-9.14) at age 75-84, and 14.5(9.47-22.1)among patients ≥ 85 years, with no major differences across different types of admission or discharge diagnoses. Conclusion: Elderly ACS patients were less likely to present with ST-elevation but had substantial in-hospital mortality, yet they were markedly less intensively treated and investigated. Aims: Age is one of the most powerful determinants of prognosis in myocardial infarction, but there is comparatively little recent data across the whole spectrum of acute coronary syndromes (ACS). We examined the impact of increasing age on clinical presentation and hospital outcome in a Large samples of patients with ACS. Methods and results: Patients (n = 10 253) from the Euroheart ACS survey in 103 hospitals in 25 countries were investigated. There was a significant inverse association between the age and the likelihood of presenting with ST-elevation . For each decade of life, the odds of presenting with ST-elevation decreased by 0.82 [95% confidence interval (CI) 0.79-0.84]; P <0.0001. Elderly patients were significantly less often treated by cardiologists, and less extensively investigated, and Compared with ST-elevation ACS, less likely to be treated with reperfusion. Compared with patients <55 years, the odds ratios of hospital mortality were 1.87 (1.21-2.88) at age 55-64, 3.70 (2.51- 5.44) at age 65-74, 6.23 (4.25-9.14) at age 75-84, and 14.5 (9.47-22.1) among patients ≥ 85 years with no major differences across different types of admission or discharge diagnoses. Conclusion: Elderly ACS patients were less likely to present with ST-elevation but had substantial in-hospital mortality, yet they were markedly less intensively treated and investigated.