Relationship between electrocardiogram heart rate variability and myocardial fibrosis in patients with acute myocardial infarction and its value in predicting the occurrence of malignant arrhythmias

HU Shi-rong; XIAO Min; YE Jiu-ming

doi:10.3969/j.issn.1672-5301.2025.11.012

Abstract：Objective To explore the relationship between the electrocardiogram heart rate variability(HRV)and myocardial fibrosis in patients with acute myocardial infarction(AMI)and its value in predicting the occurrence of malignant arrhythmias.Method A total of 180 patients with AMI admitted to Guanghan City People's Hospita from October 2023 to September 2024 were selected and underwent 24-hour dynamic electrocardiogram examination and their HRV parameters were recorded.They were followed up for 30 days and divided into the myocardial fibrosis group(n=38)and non myocardial fibrosis group(n=142)according to whether myocardial fibrosis occurring.The HRV parameters of the two groups were compared.At the same time,they were divided into the malignant arrhythmia group(n=57)and non malignant arrhythmia group(n=123)according to whether malignant arrhythmia occurring.The general information and HRV parameters of the two groups were compared.Multiple factor Logistic regression model was used to analyze the risk factors for malignant arrhythmia in AMI patients,and ROC curves were established to analyze the predictive value of each risk factor for malignant arrhythmia in AMI patients.Result The standard deviation of mean normalized NN interval(SDANN),standard deviation of all sinus rhythm NN intervals(SDNN)and the root mean square of continuous differences(RMSSD)in the malignant arrhythmia group were lower than those in the non malignant arrhythmia group.The SDANN,SDNN and RMSSD in the myocardial fibrosis group were lower than those in the non myocardial fibrosis group,and the differences were statistically significant(P<0.05).The levels of cardiac troponin I(cTnI)and creatine kinase MB(CK-MB)in the malignant arrhythmia group were higher than those in the non malignant arrhythmia group,and the differences were statistically significant(P<0.05).The lower SDANN、SDNN、RMSSD and the higher cTnI and CK-MB levels were the independent risk factor for the occurrence of malignant arrhythmia(P<0.05).The AUC values for the joint prediction of the SDANN,SDNN,RMSSD,cTnI and CK-MB were 0.865,0.812,0.738,0.834,0.799 and 0.965 respectively,with the sensitivities of 0.821,0.772,0.520,0.667,0.737 and 0.895 respectively,and the specificities of 0.807,0.719,0.895,0.878,0.756 and 0.919 respectively.These indicated that the joint multi-index prediction had the best performance,with good sensitivity and specificity.Conclusion The HRV parameters of AMI patients are closely related to the occurrence of myocardial fibrosis and malignant arrhythmia.The reduction of HRV parameters such as the SDANN,SDNN and RMSSD are the important biomarkers for predicting malignant arrhythmias.The elevations of cardiac injury markers such as the cTnI and CK-MB also increase the risk of malignant arrhythmia.The combining HRV parameters with myocardial injury markers can improve the predictive efficiency of malignant arrhythmia occurrence,providing a basis for clinical risk assessment and treatment decision-making.