The relationship between heart rate turbulence and heart rate variability

Objective:To investigate the correlation between heart rate turbulence(HRT)and heart rate variability(HRV)indices,and the impact of mean R-R interval,β-blocker and other factors on HRV and HRT.Methods:76 postinfarction patients were recruited.24-hour,three-lead ambulatory electrocardiography was performed in all subjects for the analysis of HRV(including SDNN,PNN50,RMSSD,HF,LF)and HRT(including TO and TS).And the general clinical data of each case were collected.Results:TS was positively correlated with SDNN(r=0.559,P0.001),PNN50(r=0.511,P0.001),RMSSD(r=0.515,P0.001),HF(r=0.644,P0.001).TO was inversely correlated with SDNN(r=-0.524,P0.001),PNN50(r=-0.511,P0.001),LF(r=-0.543,P0.001),HF(r=-0.412,P0.001).Both TO and TS had no correlation with the variables such as the treatment of β-blocker,mean R-R intervals,LVEF,concomitant hypertension,but there was a weak correlation between SDNN and each one of these variables.Conclusions:TS is mainly associated with the cardiac vagal efferent activity.TO may be modulated by both sympathetic and parasympathetic efferent activity.HRT is not influenced by such factors as treatment of β-blocker,mean R-R intervals,LVEF,concomitant hypertension,which may explain the reason why HRT is superior to HRV in predicting high-risk patients of SCD.