Effect of acupuncture at HT7 on heart rate variability: an exploratory study.

OBJECTIVE: To explore the effect of acupuncture at HT7 on heart rate variability (HRV) in healthy volunteers. METHODS: 120 subjects were divided into four groups using a random number table. The following groups of acupuncture interventions were used: HT7 verum acupuncture; HT7 non-penetrating sham acupuncture; acupuncture at a sham point; and no acupuncture. HRV was recorded 10 min before, during and after each stimulation using an Actiheart ECG recorder. RESULTS: The HT7 verum acupuncture group had higher very-low frequency, low frequency and high frequency components of HRV compared with the control groups during but not after acupuncture. The HT7 verum acupuncture group also had higher SD of normal intervals compared with the sham needling and no acupuncture control groups. CONCLUSIONS: Our preliminary study suggests, subject to limitations, that acupuncture at HT7 could affect cardiac autonomic neural regulation in healthy subjects, manifest as increased HRV, most likely via the parasympathetic system. TRIAL REGISTRATION NUMBER: ChiCTR-TRC-08000302.