title: 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.
authors.affiliation: Hypertension Center, The Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Nelson
authors.affiliation: Hypertension Center, The Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California; School of Nursing, University of California, Los Angeles, Los Angeles, California.
authors.forename: Mary
authors.initials: M
authors.lastname: Rezk-Hanna
authors.affiliation: Hypertension Center, The Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California.
authors.forename: Florian
authors.initials: F
authors.lastname: Rader
authors.affiliation: Hypertension Center, The Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California.
authors.forename: O'Neil R
authors.initials: OR
authors.lastname: Mason
authors.affiliation: Hypertension Center, The Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California.
authors.forename: Xiu
authors.initials: X
authors.lastname: Tang
authors.affiliation: Hypertension Center, The Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California.
authors.forename: Sarah
authors.initials: S
authors.lastname: Shidban
authors.affiliation: Hypertension Center, The Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California.
authors.forename: Ryan
authors.initials: R
authors.lastname: Rosenberry
authors.affiliation: Division of Clinical Pharmacology and Experimental Therapeutics, Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California.
authors.forename: Neal L
authors.initials: NL
authors.lastname: Benowitz
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Medicine, The David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California.
authors.forename: Donald P
authors.initials: DP
authors.lastname: Tashkin
authors.affiliation: Department of Biomathematics, The David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Elashoff
authors.affiliation: Knight Cardiovascular Institute, Oregon Health & Science University, Portland, Oregon.
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Lindner
authors.affiliation: Hypertension Center, The Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California. Electronic address: Ronald.Victor@cshs.org.
authors.forename: Ronald G
authors.initials: RG
authors.lastname: Victor
mesh_terms: D000293:Adolescent; D000328:Adult; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000502:physiology*; D004452:Echocardiography; D004562:Electrocardiography; D064368:Healthy Volunteers; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000502:physiology*; D009206:Myocardium / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology*; D012039:Regional Blood Flow / Q000502:physiology; D012907:Smoking / Q000009:adverse effects*; D014664:Vasodilation; D055815:Young Adult