Objectives This study sought to compare the in-hospital prognostic values of the original and updated GRACE(Global Registry of Acute Coronary Events) risk score(RS) and the AR-G(ACTION [Acute Coronary Treatment and Intervention Outcomes Network] Registry and the GWTG [Get With the Guidelines] Database) RS in acute coronary syndromes(ACS).To evaluate the utility of recalculating risk after percutaneous coronary intervention(PCI) with newer RS models(NCDR [National Cardiovascular Data Registry] and EHS [EuroHeart Score] RS).Background Defined in 2003,GRACE is among the most popular systems of risk stratification in ACS.An updated version of GRACE has since appeared and new RS have been developed,aiming to improve risk prediction.Methods From 2004 to 2010,4,497 consecutive patients admitted to a single center in Spain with an ACS were included(32.1% ST-segment elevation myocardial infarction,19.2% unstable angina).Discrimination(C-statistic) and calibration(Hosmer-Lemeshow [HL]) indexes were used to assess performance of each RS.A comparative analysis of RS designed to predict post-PCI mortality NCDR and EHS RS versus the GRACE and AR-G RS was performed in a subgroup of 1,113 consecutive patients included in the study.Results There were 265 in-hospital deaths(5.9%).Original and updated GRACE RS and the AR-G RS all demonstrated good discrimination for in-hospital death(C-statistics:0.91,0.90 and 0.90,respectively) with optimal calibration(HL p:0.42,0.50,and 0.47,respectively) in all spectra of ACS,according to different managements(PCI vs.conservative) and without significant differences between the 3 different RS.In patients undergoing PCI,EHS and NCDR RS(C-statistic = 0.80 and 0.84,respectively) were not superior to GRACE RS(C-statistic = 0.91),albeit in the subgroup of patients undergoing PCI who were categorized as high risk using the GRACE RS,both EHS and NCDR have contributed to decrease the false positive rate generated by using the GRACE RS.Conclusions Despite having been developed over 8 years ago,the GRACE RS still maintains its excellent performance for predicting in-hospital risk of death among ACS patients. Objectives This study sought to compare the in-hospital prognostic values ​​of the original and updated GRACE (Global Registry of Acute Coronary Events) risk score (RS) and the AR-G (ACTION [ACS Coronary Treatment and Intervention Outcomes Network] Registry and the To evaluate the utility of recalculating risk after percutaneous coronary intervention (PCI) with newer RS ​​models (NCDR [National Cardiovascular Data Registry] and EHS [EuroHeart Score] RS). Background Defined in 2003, GRACE is among the most popular systems of risk stratification in ACS. An updated version of GRACE has since appeared and new RS have been developed, aiming to improve risk prediction. Methods From 2004 to 2010, 4,497 consecutive patients admitted to a single center in Spain with an ACS were included (32.1% ST-segment elevation myocardial infarction, 19.2% unstable angina). Discrimination (C-statistic) and calibration (Hosmer-Lemeshow [HL]) indexes w A comparative analysis of RS designed to predict post-PCI mortality NCDR and EHS RS versus the GRACE and AR-G RS was performed in a subgroup of 1,113 consecutive patients included in the study. Results There were 265 in-hospital deaths (5.9%). Original and updated GRACE RS and the AR-G RS all demonstrated good discrimination for in-hospital death (C-statistics: 0.91, 0.90 and 0.90, respectively) 0.42, 0.50, and 0.47, respectively) in all spectra of ACS, according to different managements (PCI vs. consumer) and without significant differences between the 3 different RS. Patients undergoing PCI, EHS and NCDR RS (C-statistic = and 0.84, respectively) were not superior to GRACE RS (C-statistic = 0.91), albeit in the subgroup of patients undergoing PCI who were categorized as high risk using the GRACE RS, both EHS and NCDR have contributed to decrease the false positive rate generated by using the GRACE RS.Conclusions Despite having been developed over 8 years ago, the GRACE RS still maintains its excellent performance for predicting in-hospital risk of death among ACS patients.