ABSTRACT
Objective To observe the change of sinus heart rate turbulence (HRT) and its relation to left ventricular systolic function (LVSF) in patients with acute coronary syndrome (ACS). Methods The 103 ACS patients and 62 healthy subjects were enrolled in this study, all of them received 24-hour Holter monitor. And the values of turbulence onset (TO), turbulence slope (TS)and heart rate variability (HRV) SDNN were calculated according the Holter records. The clinical information, left ventricular ejection fraction (LVEF) and left ventricular end diastolic diameter (LVEDD) were recorded. Then the ACS patients were divided into acute myocardial infarction (AMI)group and unable angina pectoris (UAP) group according to the cardiac enzymes and electrocardiogram. Results The value of TO was significantly higher in ACS group than in control group [(0.17±1.40)％ vs. (- 0.26±0.99)％, P＜0.05], and TS was significantly lower in ACS group than in control group [R-R interval:(0.88±2.51) ms vs. (2.60±2.76) ms, P＜0.01].There were significant differences in TS, LVEF and LVEDD between AMI group and UAP group (all P＜0.01), but there were no differences in HRV and TO between the two groups. TS was positively correlated with LVEF (r=0.21, P＜0.05), while TO was negatively correlated with LVEF (r=-0.26, P＜0.05) by Spearman correlation analysis. Conclusions HRT is significantly blunted in ACS patients and can evaluate cardiac autonomic function. It may be as a predictor of LVSF in ACS patients.