Objective: To investigate the association of fragmented QRS complex (fQRS) with cardiac autonomic nerve function and left ventricular remodeling in patients with acute ST-segment elevation myocardial infarction (STEMI). Methods: A retrospective analysis was performed on 170 STEMI patients hospitalized in the cardiology department of our hospital. According to the presence of fQRS on the ECG

patients were divided into nfQRS group (n=94) and fQRS group (n=76). Basic clinical data

24 h dynamic ECG indicators and echocardiography data were analyzed to compare the differences between the patients of the two groups. Results: Compared with the nfQRS group

the values of standard deviation of NN intervals (SDNN)

standard deviation of all 5-min average NN intervals (SDANN)

very low frequency (VLF)

low frequency (LF)

ratio of low frequency to high frequency power (LF/HF) of heart rate variability (HRV) in the fQRS group were significantly decreased (P<0.05); the left ventricular ejection fraction (LVEF) of left ventricular function of the fQRS group was significantly lower than that of the nfQRS group

while the left ventricular end-diastolic dimension (LVEDD) and N-terminal pro brain natriuretic peptide (NT-proBNP) values were significantly higher than those of nfQRS group (P<0.01). Multiple logistic regression analysis showed that after adjusting for age and gender

reduced SDNN

SDANN

VLF

LF

LF/HF

LVEF and increased NT-proBNP were risk factors for fQRS in STEMI patients. Spearman correlation analysis showed that SDNN

SDANN

VLF

LF

LF/HF

LVEF were significantly negatively correlated with fQRS in STEMI patients

while LVEDD

NT-proBNP were significantly positively correlated with fQRS (P<0.01). Conclusion: In STEMI patients with fQRS on ECG

myocardial ischemia is serious

cardiac autonomic nerve function damage is obvious

and left ventricular remodeling is significant.