The relationship between J-wave and Vagal activity in the patients who do not have structural heart disease

초록

Introduction: The relationship of a J-wave and autonomic nervous activity in the patients who do not have structural heart disease are still under investigation. We sought to investigate whether the presence of a J-wave on the surface ECG could be related to an increase of vagal activity in patients who do not have structural heart disease. Methods: This study is a retrospective study of 659 patients who did not have structural heart disease from an 18-year-old to 65-year-old who underwent a Holter ECG and a surface ECG. We compared the high frequency component (HF), the low frequency component (LF), and the ratio of LF to HF (LF/HF) on the Holter ECG between patients who have a J-wave (group1), and those who do not have a J-wave on the surface ECG (group2). Results: The presence of a J wave was observed in 93 (14.1%) patients among all patients. Age (group 1 vs group 2=46±12 vs. 44±12, p=0.205), frequency of classical cardiovascular risk factors and sex ratio were similar between the two groups. Heart rate (HR) on the surface ECG (group 1 vs. group 2=68±13 vs. 73±28, p=0.007), Average HR (69±8 vs.73±9, p=0.001) on the Holter ECG were significantly slower in the group 1. During a 24-hour period, neither LF nor HF was significantly different between the two groups. However, the LF/HF was significantly lower in the group 1 (2.09±1.34 vs 2.64±1.57, p=0.002). The rMSSD(Square root of the mean squared differences of successive NN intervals, ms) also had significantly higher values in the group 1 (33.12±11.84 vs 30.36±12.29, p=0.044). Conclusions: In patients who do not have structural heart disease, the presence of a J-wave was associated with a slow heart rate and an increase in vagal activity, independently.