Acute Effect of Hookah Smoking on the Human Coronary Microcirculation

Abstract

Hookah (water pipe) smoking is a major new understudied epidemic affecting youth. Because burning charcoal is used to heat the tobacco product, hookah smoke delivers not only nicotine but also large amounts of charcoal combustion products, including carbon-rich nanoparticles that constitute putative coronary vasoconstrictor stimuli and carbon monoxide, a known coronary vasodilator. We used myocardial contrast echocardiography perfusion imaging with intravenous lipid shelled microbubbles in young adult hookah smokers to determine the net effect of smoking hookah on myocardial blood flow. In 9 hookah smokers (age 27 – 5 years, mean – SD), we measured myocardial blood flow velocity (β), myocardial blood volume (A), myocardial blood flow (A × β) as well as myocardial oxygen consumption (MVO2) before and immediately after 30 minutes of ad lib hookah smoking. Myocardial blood flow did not decrease with hookah smoking but rather increased acutely (88 – 10 to 120 – 19 a.u./s, mean – SE, p = 0.02), matching a mild increase in MVO2 (6.5 – 0.3 to 7.6 – 0.4 ml·minute−1, p <0.001). This was manifested primarily by increased myocardial blood flow velocity (0.7 – 0.1 to 0.9 – 0.1 second−1, p = 0.01) with unchanged myocardial blood volume (133 – 7 to 137 – 7 a.u., p = ns), the same pattern of coronary microvascular response seen with a low-dose β-adrenergic agonist. Indeed, with hookah, the increased MVO2 was accompanied by decreased heart rate variability, an indirect index of adrenergic overactivity, and eliminated by β-adrenergic blockade (i.v. propranolol). In conclusion, nanoparticle-enriched hookah smoke either is not an acute coronary vasoconstrictor stimulus or its vasoconstrictor effect is too weak to overcome the physiologic dilation of coronary microvessels matching mild cardiac β-adrenergic stimulation.

Water Pipe (Hookah) Smoking and Cardiovascular Disease Risk: A Scientific Statement From the American Heart Association

“…In general, in young, healthy individuals, smoking tobacco via a water pipe for 15 to 30 minutes increases heart rate by 6 to 13 beats per minute, systolic blood pressure by 3 to 16 mm Hg, [88][89][90][91] and diastolic blood pressure by 2 to 14 mm Hg. 88,89,91 These changes are accompanied by a decrease in heart rate variability [91][92][93] and a modest increase in coronary blood flow. 93 Water pipe tobacco smoking increases myocardial oxygen demand similar to the effects of cigarette smoking.…”

“…88,89,91 These changes are accompanied by a decrease in heart rate variability [91][92][93] and a modest increase in coronary blood flow. 93 Water pipe tobacco smoking increases myocardial oxygen demand similar to the effects of cigarette smoking. 93 Overall, the short-term cardiovascular effects are consistent with the sympathomimetic effects of nicotine, which are mediated by βadrenergic activation.…”

“…93 Water pipe tobacco smoking increases myocardial oxygen demand similar to the effects of cigarette smoking. 93 Overall, the short-term cardiovascular effects are consistent with the sympathomimetic effects of nicotine, which are mediated by βadrenergic activation. Indeed, in a double-blind placebo-controlled study, no changes in heart rate were observed when a flavor-matched, tobacco-free preparation was smoked.…”

“…94 Like-wise, the decrease in heart rate variability with water pipe smoking was prevented by β-adrenergic blockade. 93 Therefore, the short-term hemodynamic effects of water pipe tobacco smoking may be attributed to nicotine-induced β-adrenergic stimulation.…”

Cardiovascular effects of waterpipe smoking: a systematic review and meta-analysis

“…Potential WPS effects on cardiac autonomic regulation were investigated in three experimental studies (Al-Kubati et al, 2006;Cobb et al, 2012;Nelson et al, 2016), revealing markedly impaired HR/BP variation and baroreflex sensitivity after one WPS session (P < 0.05). This effect was independent of nicotine content when tobacco-free-WPS was used (Cobb et al, 2012).…”