Skip to main content
. Author manuscript; available in PMC: 2017 Nov 16.
Published in final edited form as: Am J Cardiol. 2016 Mar 18;117(11):1747–1754. doi: 10.1016/j.amjcard.2016.03.007

Figure 3.

Figure 3

Effect of hookah smoking on heart rate variability before and after β-adrenergic blockade (i.v. propranolol). Panels illustrate heart rate, normalized high frequency power (HFnu), normalized low frequency power (LFnu), and the LF/HF ratio before (white bars) and immediately after (black bars) 30 minutes of hookah smoking with and without β blockade. Summary data for 4 subjects reported as mean ± SE, *p <0.05. HFnu = high frequency normalized units; LFnu = low frequency normalized units.