Table 5

Time effects after myocardial infarction

Period IPeriod IIPeriod III
24 Hour RR interval variability
RR means (ms)1047 (33)1015 (28)1063 (39)
 SDNN (ms)158 (9)185 (31)154 (9)
 1n ULF9.88 (0.12)9.84 (0.13)9.83 (0.13)
 1n VLF7.27 (0.18)7.34 (0.14)7.27 (0.16)
 1n LF6.49 (0.18)6.49 (0.16)6.38 (0.19)
 1n HF6.06 (0.15)5.86 (0.18)5.75 (0.19)
Short term RR interval variability
Supine rest
 RR mean (ms)1108 (26)1100 (32)1078 (29)
 SDNN (ms)34 (2)40 (3)33 (2)
 LF/HF ratio1.01 (0.21)1.32 (0.22)1.63 (0.39)
Head up tilt
 RR mean (ms)1071 (29)1073 (32)1053 (30)
 SDNN (ms)36 (2)35 (3)34 (2)
 LF/HF ratio2.12 (0.49)1.86 (0.46)2.08 (0.59)
Mental stress
 RR means (ms)1060 (23)1084 (31)1092 (31)
 SDNN (ms)30 (2)31 (3)33 (2)
 LF/HF ratio1.66 (0.36)2.14 (0.49)2.06 (0.54)
Exercise test
Exercise duration (min)9.60 (0.54)10.40 (0.57)10.60 (0.62)3-150
Maximum work load (W)93 (3.5)98 (3.8)99 (4.1)3-150
PeakV˙o 2(ml/min)1396 (58)1462 (61)1505 (63)3-150
BRS (ms/mm Hg)9.8 (0.86)11.5 (1.24)12.2 (1.84)
Noradrenaline (pg/ml)499 (66.2)478 (39.3)483 (48.4)
Adrenaline (pg/ml)0.424 (0.063)0.429 (0.058)0.603 (0.097)
  • Values are means (SEM).

  • 3-150 p < 0.05 between periods I and III.

  • SDNN, standard deviation of all normal RR values; ULF, ultra low frequency power; VLF, very low frequency power; LF, low frequency power; HF, high frequency power; 1n, natural logarithm; BRS, baroreflex sensitivity; V˙o 2, oxygen uptake.