To investigate the relationship between QRS wave lengthening and myocardial injury in patients with acute ST-segment elevation myocardial infarction (STEMI).

Retrospective analysis of patients diagnosed with coronary artery disease from February 2017 to November 2019 was conducted and a total of 90 cases were involved in this study. According to the QRS whether the wavelength was prolonged or not, the patiants were divided into prolonged (n=52) and non-prolonged (n=38) groups, and the QRS prolongation and clinical characteristics of the relationship were analyzed, and myocardial injury index CTnI, CK-MB and Myo were detected. Levels of cardiac function LVEF, LVFS and LVEDd were analyzed for correlation between prolonged time and indices related to myocardial injury.

Serum CTnI, CK-MB and Myo indexes were significantly higher in the QRS prolonged group than that in the non-prolonged group, and the differences were significant Statistically significant (P<0.05); the levels of LVEF and LVFS in the QRS extension group were significantly lower than those in the non-prolonged group; LVEDd was significantly higher than in the non-prolonged group, and the difference was statistically significant (P<0.05); QRS prolongation levels was significantly positively correlated (P<0.05) with serum CTnI, CK-MB, and Myo indexes, and there was a significantly negative correlation (P<0.05) between the levels of LVEF and LVFS, and a significantly positive correlation with the level of LVEDd (P<0.05).

ECG QRS prolongation is positively correlated with the degree of myocardial damage in STEMI patients, and monitoring the QRS wave forms of the ECG helps to assess the extent of myocardial damage in STEMI patients.