Table 3.

MAP and CBFV variability measures

	Supine		70° Head-Up Tilt
	POTS subjects	Control subjects	POTS subjects	Control subjects
MAP variability	5±0.6	7±1	16±1*	12±3
LF component	2±0.3	2±0.2	10±1*	8±2*
HF component	0.8±0.2	0.3±0.1	2±0.3*	1±0.2*
CBFV variability	10±2	10±2	17±4	14±3
LF component	3±0.9	3±0.6	9±2*	6±1
HF component	1±0.3	1±0.2	3±0.7*	2±0.5*
αCBF, ms/mmHg	0.8±0.1	1±0.2	1±0.1*	1±0.1
LF
Coherence	0.53±0.04	0.54±0.08	0.90±0.02*	0.81±0.05*
Gain, mmHg·cm−1·s−1	0.7±0.1	0.7±0.1	1.08±0.10*	1.12±0.10
Phase, °	39±5†	64±6	42±4	48±7
HF
Coherence	0.65±0.04	0.52±0.07	0.83±0.05*	0.60±0.09
Gain, mmHg·cm−1·s−1	0.8±0.1	0.7±0.1	0.9±0.1	1±0.2
Phase, °	15±4	−0.3±6	11±2	5±5

Values are means ± SE.

^*P < 0.05 compared with supine values within the same group;

^†P < 0.05 compared with the control group.