Risk score comparison of outcomes in patients presenting with ST-elevation myocardial infarction treated with percutaneous coronary intervention

Background: Accurate risk stratification is important in the management of acute coronary syndrome (ACS) patients. Several risk scores have been developed to stratify patients hospitalized with ACS. Aim: To compare the prognostic value of three risk scores used to determine the risk for secondary events in patients diagnosed with ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI). Methods: A retrospective analysis of patients with an ACS experiencing a STEMI treated with PCI presenting to a Kaiser Permanente Foundation Hospital in Northern California from January 2007 to January 2008 (n=186). For each patient, the Thrombolysis in Myocardial Infarction (TIMI), Controlled Abciximab and Device Investigation to Lower Late Angioplasty complications (CADILLAC), and Global Registry for Acute Coronary events (GRACE) risk scores were calculated and predictive ability was analysed using the area under the curve or C statistic method. Results: The CADILLAC, TIMI, and GRACE risk scores all had high predictive accuracy for a major cardiac event in hospital, with C statistics ranging from 0.63 to 0.718 with the CADILLAC risk score superior. For non-major cardiac events in hospital, the three risk scores were similar in accuracy for predictability, with C statistics ranging from 0.62 to 0.66. Conclusions: Risk stratification of patients with STEMI undergoing primary percutaneous coronary intervention can be done using all three risk scores. In our analysis, the CADILLAC and GRACE score was more predictive for major cardiac events in hospital and CADILLAC and TIMI for major cardiac events at 1 year.