Objective To study the value of fragmented QRS wave (fQRS) combined with the Global Registry of Acute Coronary Events(GRACE) score in predicting cardiac death during hospitalization and within 6 months after discharge in patients with acute non-ST segment elevation myocardial infarction (NSTEMI).

Methods A total of 334 NSTEMI patients were enrolled, patients were divided into fQRS wave group (n=145) and non-fQRS wave group (n=199) according to the presence or absence of fQRS in the ECG at admission. According to different GRACE scores, the patients were divided into low risk group (112 cases), medium risk group (126 cases) and high risk group (106 cases). Cardiac deaths during hospitalization and within 6 months afterdischarge were observed. Patients' indicators and occurrence of death events among different groups were compared. Receiver Operating Characteristic (ROC) curve was used to compare the predictive values of fQRS, GRACE score alone and their combination in predicting short-term cardiac death events.

Results A total of 344 patients with NSTEMI were followed up for (5.55±1.37) months, and 24 patients had cardiac death events. The proportions of patients with type 2 diabetes mellitus, pre-myocardial infarction, the triple-vessel disease and the level of NT-proBNP in the fQRS wave group were higher than those in the non-fQRS wave group, the level of LVEF in the fQRS wave group was lower than that in wave non-fQRS group (P < 0.05). Ratio of cardiac death in the fQRS wave group was higher than that in the non-fQRS wave group (10.34% versus 4.51%, P < 0.05). The incidence of cardiac death in the high risk group was significantly higher than that in the middle risk group and the low risk group (P < 0.05). Multivariate Logistics regression analysis showed that fQRS wave and GRACE score were the risk factors of short-term cardiac death in patients with NSTEMI (OR=2.739, 95%CI, 1.123 to 6.637, P=0.002; OR=10.861, 95%CI, 2.426 to 48.621, P=0.027). The area under the ROC curve in predicting cardiac death in the fQRS wave group was 0.609 (95%CI, 0.556 to 0.661), was 0.735 by GRACE score (95%CI, 0.685 to 0.781), and was 0.748 by combined prediction (95%CI, 0.698 to 0.793). Further comparison of the area under the ROC curve showed that the area under the ROC curve of combined detection was larger than that by GRACE score or fQRS wave alone(P < 0.001).

Conclusion FQRS wave, GRACE score and their combination can predict short-term cardiac death in patients with NSTEMI. The fQRS wave combined with GRACE score has better predictive value for short-term cardiac death in patients with NSTEMI.