Effect of Acute Mental Stress on Heart Rate and QT Variability in Postmyocardial Infarction Patients
Table 3
Nonspectral RR, SPB, and QT data obtained from the analysis of the 10-beat segment collected during SBP maximum peak in the three study groups.
Variables
LVEF ≤ 45% group N: 20
LVEF ≥ 50% group N: 10
Control group N: 10
P
LVEF ≤ 45% group N: 20
LVEF ≥ 50% group N: 10
Control group N: 10
P
Baseline
During Anger Recall test
SBP, mmHg
113 ± 20‡
133 ± 30‡
127 ± 25‡
Ns
131 ± 25
145 ± 31
139 ± 27
Ns
RR mean, ms
877 ± 143‡
855 ± 93‡
1013 ± 110‡
Ns
824 ± 139
808 ± 76
886 ± 102
Ns
RR variance, ms2
312 [462]†
205 [827]*
538 [3385]‡
.032
307 [1038]†
385 [1930]*
3426 [3781]
.004
QT mean, ms
372 ± 49
351 ± 46
382 ± 30‡
Ns
366 ± 47
340 ± 39
364 ± 31
Ns
QT variance, ms2
27 [54]
18 [26]
11 [18]
Ns
45 [75]
27 [28]
18 [20]
Ns
QTVI
0.01 [0.97]†§
−0.77 [2.07]
−0.84 [0.63]‡
.003
−0.41 [1.80]†
−0.50 [1.45]*
−1.35 [0.60]
.003
Values are expressed as mean ± SD or median [interquartile range 75th percentile–25th percentile]. Abbreviations as in Tables 1 and 2.
‡ data at baseline versus data after Anger Recall Test; † LVEF ≤ 45% Group versus Controls; § LVEF ≤ 45% Group versus LVEF ≥ 50% Group; * LVEF ≥ 50% Group versus Controls.
