Value of TIMI and GRACE score systems in predicting in-hospital events in Chinese patients with non-STsegment elevation myocardial infarction / 第二军医大学学报

ABSTRACT

Objective To evaluate the clinical value of thrombolysis in myocardial infarction (TIMI) and global registry of acute coronary events (GRACE) score systems in predicting the risk of in-hospital events in Chinese patients with non-ST-segment elevation myocardial infarction (NSTEMI). Methods Patients with NSTEMI admitted to the Department of Cardiovasology, Renji Hospital, Shanghai Jiao Tong University School of Medicine between Jan. 1 to Dec. 1, 2017 were consecutively enrolled. The end-point events were in-hospital mortality, reinfarction, heart failure, cardiac skock, and sudden cardiac arrest. Patients were scored by TIMI and GRACE score systems on hospital admission, and receiver operating characteristic (ROC) curve was used to evaluate the value of the two score systems and the combination of both in predicting in-hospital events. TIMI score was used to screen all the patients, and the TIMI medium-risk patients were further divided into GRACE high-risk subgroup (GRACE score≥140) and GRACE non-high-risk subgroup (GRACE score<140). The incidence of in-hospital events was compared between the two subgroups. Results A total of 232 patients were included in this study (163 males and 69 females, with an average age 66.1 years and 95% confidence interval [CI] 64.6-67.6 years). TIMI score grouped 69 (29.7%), 142 (61.2%) and 21 (9.1%) patients into low-, medium- and high-risk, and the incidence rates of in-hospital events were 14.5% (10/69), 24.6% (35/142) and 33.3% (7/21), respectively. GRACE score grouped 41 (17.7%), 85 (36.6%) and 106 (45.7%) paitents into low-, medium- and high-risk, and the incidence rates of in-hospital events were 7.3% (3/41), 11.8% (10/85) and 36.8% (39/106), respectively. GRACE score and TIMI score both demonstrated good discrimination and GRACE performed better for in-hospital events (area under curve [AUC] 0.81 vs 0.62, P<0.001). Further subgrouping the TIMI medium-risk group, we found that GRACE high-risk subgroup had significantly higher incidence rate of in-hospital events than the GRACE non-high-risk subgroup (38.2% [29/76] vs 9.1% [6/66], odds ratio 6.2, 95% CI 2.4-16.1, P<0.001). Combination of TIMI and GRACE scores improved the predictive value of in-hospital events (AUC=0.71, 95% CI 0.65-0.77), with a favorable higher positive predictive value than that of TIMI or GRACE score alone (37.1% vs 33.3% and 36.8%). Conclusion GRACE score has better predictive accuracy than TIMI score in Chinese NSTEMI patients, but sacrifices simplicity. The combination of GRACE and TIMI scores is an easy and effective discriminative tool in predicting in-hospital events in Chinese NSTEMI patients.