Characteristics of Deceleration Capacity and Heart Rate Variability in Patients With Vasovagal Syncope / 中国循环杂志

ABSTRACT

Objective: To quantitatively evaluate the abnormal tense of parasympathetic nerve via measuring the heart rate deceleration capacity (DC) and heart rate variability (HRV) in patients with vasovagal syncope (VVS). Methods: Our research included 2 groups VVS group,n=28 patients with positive head-up tilt test treated in our hospital from 2013-06 to 2014-08 and Control group,n=30 patients without cardiovascular disorders. The DC and HRV were examined and compared between 2 groups. Results:① The overall deceleration capacity (ODC) (9.4 ± 2.9) ms and daytime deceleration capacity (DDC) (8.9 ± 2.9) ms in VVS group were higher than those in Control group (7.5 ± 2.5) ms and (7.5 ± 2.5) ms respectively,P1 than those in Control group (9/28, 32.1% vs 2/30, 6.7%),P=0.019.③ The SDNN (139.8 ± 34.0) ms, SDSD (29.9 ± 15.7) ms and rMSSD (40.9 ± 18.8) ms in VVS group were higher than those in Control group, (115.5 ± 29.4) ms, (21.8 ± 6.6) ms and (28.9 ± 8.4) ms respectively,P Conclusion: VVS patients have abnormally increased indexes of DC and HRV, HDC is the predictor for vasovagal syncope occurrence.