Objective: To analyze HRV at rest in healthy people and in patients with acute myocardial infarction (AMI) and how does it change during aerobic exercise.
Methods: The heartbeat signal was recorded beat to beat along 15 minutes at rest and 15 minutes while pedalling in 10 healthy and active men (H group) and 10 cardiac patients (C group). The statistical parameters in time domine were calculated as well as the spectral analysis applying the Fast Fourier Transform (FFT) and the Poincare’s graphic analysis (PGA).
Results: At rest, H group have an average SDRR (standard deviation of RR intervals) of 71.24 msec, a pRR50 (percent of differences higher than 50 msec in RR intervals) of 9.97 % and a PGA called “comet-type”. The C group have a SDRR of 36.69 msec, a pRR50 of 1.69 %, and a PGA “torpedo-type”. These data show a low or moderate risk for healthy people and a high risk for patients. The FFT analysis lies into the very low frequency (VLF) zone in both groups. During exercise, H group shows a significant decrease in all parameters; the PGA turns to “torpedo-type” and the FFT kept into the VLF zone. However, C group is characterized by the maintenance of pRR50, no change in PGA and a second peak in FFT in the high frequency zone.
Conclusion: The HRV at rest and during aerobic exercise follows a different pattern in healthy people and in patients and it provides further information about the performance during exercise.
- autonomous modulation
- heart rate variability
- risk assessment