Table 1

Clinical characteristics, supine haemodynamic measurements, and heart rate variability indices of subjects with a positive head up tilt test (HUT) compared with those with a negative test

Positive HUT (n = 42)Negative HUT (n = 27)p Value
Sex (F/M)22/2012/15NS
Age (years)39 (18)42 (19)NS
Number of syncopal episodes3.6 (5.4)4.5 (7.0)NS
Associated presyncope29/4218/27NS
Injury17/4210/27NS
Seizures6/423/27NS
Heart rate (beats/min)71 (14)70 (10)NS
Systolic BP (mm Hg)130 (24)136 (21)NS
Diastolic BP (mm Hg)76 (16)79 (16)NS
LFPP(beats/min2)6.7 (3.4)6.8 (4.1)NS
HFPP (beats/min2)2.8 (1.6)2.7 (1.7)NS
LFPP/HFPP 2.7 (1.5)2.8 (1.5)NS
LFBA (beats/min2/Hz)0.5 (0.3)0.5 (0.3)NS
HFBA(beats/min2/Hz)0.4 (0.2)0.4 (0.2)NS
LFBA/HFBA 1.3 (0.5)1.3 (0.5)NS
  • Values are mean (SD) or n.

  • BA, bandwidth area; BP, blood pressure; HF, high frequency (0.15 to 0.4 Hz); LF, low frequency (0.04 to 0.15 Hz); PP, power peak.