Deceleration Capacity of Heart Rate After Acute Altitude Exposure

摘要

Hamm, Wolfgang, Lukas von Stulpnagel, Mathias Klemm, Monika Baylacher, Konstantinos D. Rizas, Axel Bauer, and Stefan Brunner. Deceleration capacity of heart rate after acute altitude exposure. High Alt Med Biol 00:000-000, 2018. Background: The autonomic nervous system plays a crucial role in adaptive changes after high-altitude exposure. Deceleration capacity (DC) of heart rate is an advanced marker of heart rate variability (HRV) that predominantly reflects the vagal activity of the cardiac autonomic nervous system. The impact of high-altitude exposure on DC has not been investigated yet. Methods: In eight healthy individuals we performed a high-resolution digital 30-min electrocardiography in Frank leads configuration at baseline (521m altitude), immediately after ascent to the Environmental Research Station Schneefernerhaus (UFS) at Zugspitze (2650m altitude) and after a sojourn of 24 hours at this altitude. DC of heart rate was assessed using customized software. In addition, standard parameters of HRV were assessed. Results: DC decreased significantly from 10.20.8ms to 8.9 +/- 1.0ms (p0.05) after acute altitude exposure. After a sojourn of 24 hours at high altitude, DC remained low at 8.6 +/- 1.2ms. There were no significant changes in standard parameters of HRV. Conclusion: Our findings show for the first time a decrease of DC of heart rate providing a novel insight into the dysbalance of autonomic nervous system at high altitude.