Daytime and night time RR interval variability
| Day | Night | ||||||
|---|---|---|---|---|---|---|---|
| Atenolol | Metoprolol CR | Atenolol | Metoprolol CR | ||||
| RR mean (ms) | 1033 (32)† | 929 (24) | 1194 (35)‡ | 1146 (32)‡ | |||
| SDNN (ms) | 109 (6) | 104 (6) | 97 (6) | 97 (7) | |||
| LF (ms2/Hz) | 792 (163) | 584 (94) | 1287 (218) | 1225 (240) | |||
| 1n LF | 6.16 (0.16) | 6.02 (0.16) | 6.70 (0.18)‡ | 6.58 (0.20)‡ | |||
| HF (ms2/Hz) | 458 (67) | 295 (45) | 749 (127) | 723 (159) | |||
| 1n HF | 5.77 (0.15)† | 5.25 (0.17) | 6.18 (0.16)‡ | 5.99 (0.19)‡ | |||
| LF/HF ratio | 1.78 (0.16) | 2.96 (0.55) | 2.25 (0.30) | 2.31 (0.31) | |||
| 1n LF/HF | 0.45 (0.11)2-150 | 0.74 (0.13) | 0.52 (0.13) | 0.59 (0.11) | |||
Values are means (SEM)
↵2-150 p < 0.05, †p < 0.005 between treatments; ‡p < 0.005 between day and night.
SDNN, standard deviation of all normal RR values; LF, low frequency power; HF, high frequency power; 1n, natural logarithm.