Relationship between Jwave and vagal activity in the patients who do not have structural heart disease

초록

Jwave has been associated with an increase of vagal activity in the patients with idiopathic ventricular fibrillation in a few studies to date. However, the relationship of a Jwave 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 Jwave on the surface ECG could be related to an increase of vagal activity in patients without structural heart disease. This study is a retrospective study of 684 patients without structural heart disease who underwent a Holter ECG and surface ECG. The patients were divided into 2 groups based in presence of Jwave on surface ECG: patients with Jwave (group 1) and without Jwave (group 2). We compared heart rate variability (HRV) reflecting autonomic nervous activity using the 24Holter ECG between two groups. The presence of Jwave on surface ECG was observed in 92 (13.4%) patients among all patients. There were no significant differences in baseline characteristics including age, gender and frequency of classical cardiovascular risk factors between patients between group 1 and group 2. Heart rate (HR) was significantly slower in group1 than group2 (p=0.031). The ratio of LF to HF (LF/HF) was significantly lower in group 1 compared with group 2 (p=0.001). The rMSSD also was significantly higher in group1 than group 2 (p=0.047). In multivariate regression analysis, male, HR and LF/HF remained independent determinants for presence of Jwave (p=0.039, p=0.036 and p<0.001, respectively). In patients who do not have structural heart disease, the presence of a Jwave was associated with a slow heart rate, male and an increase in vagal activity, independently.