Table 2.
Variables used for assessment of CAN.
| Frequency domain variables | All patients | Presence of CAN | Absence of CAN | p |
|---|---|---|---|---|
| VLF (ms2) | 395 (11.4–8159) | 154.5 (11.4–1308) | 676 (48.9–8159) | 0.000 |
| LF (ms2) | 301 (2.1–4568) | 50.5 (2.1–2899) | 565 (37.6–4568) | 0.000 |
| HF (ms2) | 244 (3.9–8381) | 43 (3.9–6590) | 463 (16.3–8381) | 0.000 |
| VLF (%) | 38.4 ± 18.9 | 51 (12.1–89.5) | 33.6 (7.9–84.5) | 0.000 |
| LF (%) | 27.4 ± 11.9 | 24 ± 11.7 | 28.9 ± 11.8 | 0.019 |
| HF (%) | 29 (4.1–74.2) | 19.8 (4.1–63.9) | 30.2 (3.7–76.5) | 0.003 |
| LF/HF ratio | 0.97 (0.1–27.9) | 1.1 (0.1–8.4) | 1 (0.1–27.9) | 0.509 |
| TIME DOMAIN VARIABLES | ||||
| RR min (ms) | 676 (30–1127) | 663.5 (502–1127) | 688 (30–1052) | 0.297 |
| RR max (ms) | 903 (597–12266) | 760.5 (597–2854) | 943 (734–12266) | 0.000 |
| RRNN (ms) | 799 547–1378) | 707 (547–1195) | 817 (618–1378) | 0.000 |
| SDNN (ms) | 32 (4–155) | 14 (4–155) | 40 (13–147) | 0.000 |
| RMSSD (ms) | 23 (1–157) | 8.5 (1–157) | 30 (7–140) | 0.000 |
| CV (%) | 4 (0.7–21.9) | 2 (0.7–21.9) | 5.1 (1.6–15.5) | 0.000 |
| TP (ms) | 1185 (26–15880) | 377.5 (26–10797) | 2125 (192–15880) | 0.000 |
| pNN50 | 1.59 (0–77.1) | 0 (0–13.2) | 7.7 (0–77.1) | 0.000 |
| CARDIOVASCULAR REFLEX TESTS (GOLD STANDARD) | ||||
| Max–min ratio | 1.36 (1.01–2.2) | 1.15 (1.01–1.9) | 1.44 (1.09–2.2) | 0.000 |
| Valsalva ratio | 1.71 (1.04–3.74) | 1.37 (1.04–2.54) | 1.9 (1.39–3.74) | 0.000 |
| E:I ratio | 1.36 (0.98–2.28) | 1.1 (0.98–1.75) | 1.45 (1.12–2.28) | 0.000 |
| Decrease in sBP (mmHg) | 3 (−27–35) | 7.5 (−27–35) | 2 (−20–17) | 0.000 |
| Decrease in sBP ≥20 mmHg, yes, n (%) | 10 (6.6) | 10 (6.6) | 0 | 0.000 |
RR min, RR minimum; RR max, RR maximum; RRNN, mean RR intervals; SDNN, standard deviation of all normal to normal RR intervals; CV, coefficient of variation; RMSDD, the root mean squared successive difference between adjacent RR intervals; TP, total power; pNN50, percentage of intervals between consecutive normal beats that exceed 50 ms; VLF, very low frequency; LF, low frequency; HF, high frequency; E:I ratio, expiration to inspiration ratio; Valsalva ratio, Max: min ratio, maximum to minimum ratio; sBP, systolic blood pressure.
The data are presented as counts (percentage), means ± SD, or medians (minimum/maximum).