TABLE 2.
Average HR and SBP during the HUT tests.
| POTS n = 25 | Non-POTS n = 12 | |
| Pre-Tilt supine HR* (beats per minute) | 74.6 (10.20) | 74.08 (11.10) |
| HUT 1 min HR* (beats per minute) | 103.9 (13.15) | 99.2 (13.41) |
| HUT 2–4 min HR* (beats per minute) | 100.8 (13.38) | 94.3 (11.34) |
| HUT final HR* (beats per minute) | 108.6 (17.77) | 95.3 (14.49) |
| Post-Tilt supine HR* (beats per minute) | 74.9 (13.16) | 71.1 (8.68) |
| Maximal heart rate upright* (beats per minute) | 133.8 (12.19) | 126.5 (15.10) |
| Delta HR** (beats per minute) | 52 (40–70) | 34.75 (29–39) |
| Pre-Tilt supine SBP* (mmHg) | 108.7 (10.62) | 103.9 (12.56) |
| Average HUT SBP* (mmHg) | 111.1 (13.42) | 105.7 (15.32) |
| Post-Tilt supine SBP* (mmHg) | 111.4 (12.61) | 105.5 (16.29) |
*Values are means with standard deviation. **Values are means with range. POTS, subjects with postural tachycardia syndrome; non-POTS, subjects without postural tachycardia syndrome; HR, heart rate in beats per minute; SBP, systolic blood pressure in mmHg; Pre-Tilt supine, 2 min before upright position in recumbent position; HUT 1 min; during the first minute of upright position; HUT 2–4 min, from the second to fourth minutes of upright position; HUT final, during the last minute of upright position; Post-Tilt supine, from the first to third minutes after returning to the recumbent position; Average HUT, the average of the parameters during the whole time in the upright position.