Interaction between beat-to-beat variability of pulse wave velocity and blood pressure in healthy young subjects: fighter pilots and non-sporting controls.

Jana Svacinova1, Lucie Vasikova1, Radek Ligursky2, Magdalena Sudakova3, Anna Vravcova1, Michaela Bittnerova1, Tomas Fordinal1, Frantisek Garncarz1, Jan Boril4, Zuzana Nováková1
1Department of Physiology, Faculty of Medicine, Masaryk University, 2University of Defence, 3Department of Physiology, Faculty od Medicine, Masaryk University, 4University od Defence


Pulse wave velocity (PWV) indirectly reflects arterial stiffness, but it is also influenced by arterial blood pressure (BP). Aim of the study is analysis of the interaction between beat-to-beat changes of BP and PWV in dependence on postural change. Two group of healthy 23-24 years old man were measured: fighter pilots (9) and non-sporting controls (8). Continual BP in the finger (photoplethysmography) and ECG were simultaneously recorded by Finapres NOVA during two phases: supine (sup) and head-up-tilt in 45° (hut). Sequences of beat-to-beat systolic, diastolic and pulse BP (SBP, DBP, PP) were detected. Beat-to-beat PWV was evaluated from the time distance between R on ECG and the diastolic times. Gains from PWV to SBP, DBP and PP were evaluated by cross-spectral method. Gain_sbp-pwv, Gain_dbp-pwv and Gain_pp-pwv were calculated as a mean gain in the low frequency band (0,04 - 0,15 Hz). Supine Gain_sbp-pwv, Gain_dbp-pwv, Gain_pp-pwv and hut Gain_pp-pwv were significantly higher in pilots than in controls. Gain_sbp-pwv and Gain_pp-pwv in pilots increased from the sup to hut. Other comparisons of gains were not significant. During both phases, Gain_dbp-pwv and Gain_pp-pwv are higher than Gain_sbp-pwv in all group. Mean DBP and SBP did not differ. Mean PWV was lower in pilots in compare to controls, especially during hut. PWV variability in peripheral artery is a complex variable containing information about arterial stiffness, BP, vascular filling, and arterial tonus. The gain explains, which part of blood pressure mostly influences PWV changes. According to the results, PWV variability in LF band is mostly influenced by DBP and therefore PP variability. The mean PWV and gain in pilots could be given by physically challenging work influencing vascular state and autonomic control of the arterial tonus and blood volume redistribution. Supported by MUNI/A/1246/2020.