Effect of Acute Mental Stress on Heart Rate and QT Variability in Postmyocardial Infarction Patients
Figure 2
Comparison between QT variability index values at baseline (Rest) and during anger recall test (AR) in the whole postmyocardial infarction patients (post-MI pts) and healthy control subjects (Controls). (a) QT variability index values obtained with the classical method on 5 min continuous ECG epochs (QTVI). (b) QT variability index values obtained from a 10-beat segment around the presumed maximum sympathetic activation (). In the box plots, the central line represents the median distribution. Each box spans from 25th to 75th percentile points, and error bars extend from 10th to 90th percentile points.
