Effects of metronome breathing on the assessment of autonomiccontrol using heart rate variability

摘要

Analysis of Heart Rate Variability is a non-invasive quantitativetool to study the influence of the autonomic nervous system on theheart. Rapid variations in heart rate, related to breathing areprimarily mediated by the vagal limb of the autonomic nervous system.The resulting variations in heart rate are usually referred to asrespiratory sinus arrhythmia. Metronome breathing (MB) is oftenadvocated to assess more accurately vagal control. However, theadditional value of MB over SB has never been established. The authorsstudied the effect of MB (0.25 Hz) on HRV variables in 12 healthy malesubjects under stable conditions using pharmacological autonomicblockade. During MB several variables showed a lower absolute value,however a strong correlation existed between variables computed duringspontaneous breathing (SB) and MB. MB offers some, but no importantadvantages over spontaneous breathing