Table 3.
Supine spectral analysis of BP and HR variability in Long-COVID POTS and Healthy controls
| Parameters | Long-COVID POTS | Healthy | P value |
|---|---|---|---|
| N = 13 | N = 16 | ||
| RMSSD | 32.1 ± 4.6 | 48.9 ± 6.8 | 0.04 |
| SD1 | 22.8 ± 3.3 | 34.2 ± 4.9 | 0.08 |
| SD2 | 59.3 ± 5.4 | 67.7 ± 5.7 | 0.30 |
| Total Power RRI | 1671 ± 350 | 2467 ± 544 | 0.29 |
| LFRRI (ms2) | 756 ± 174 | 982 ± 274 | 0.89 |
| LFRRI n.u. | 66 ± 4 | 54 ± 4 | 0.06 |
| HFRRI (ms2) | 349 ± 105 | 851 ± 253 | 0.03 |
| HFRRI n.u. | 32 ± 4 | 46 ± 4 | 0.02 |
| LF/HF | 3.0 ± 0.7 | 1.2 ± 0.3 | 0.01 |
| LFSBP (mmHg2) | 3.3 ± 1.0 | 4.6 ± 0.8 | 0.11 |
| HFSBP (mmHg2) | 1.6 ± 0.4 | 1.8 ± 0.7 | 0.78 |
Values are means ± SEM. RMSSD indicates root mean square of standard deviations; SD1 and SD2, Pointcare plots standard deviation 1 and 2; RRI R-R interval, SBP Systolic blood pressure, LF Low frequency bands, HF High frequency bands. P values obtained using Student’s t-test or Mann-Whitney test