Electronic Cigarettes Impair Human Coronary Endothelial Function

Electronic (e-) cigarettes are claimed—but unproven—to be less harmful than standard tobacco cigarettes, which are well known to impair coronary endothelial function and constitute a major cardiovascular risk factor. To determine whether e-cigarettes cause impairment in human coronary endothelial function, we compared effects of tobacco cigarette smoking and e-cigarette use to blunt the normal increase in myocardial blood flow (MBF) quantified by contrast enhanced echocardiography perfusion imaging, induced by the exercise pressor reflex (post-handgrip forearm vascular occlusion). The exercise pressor reflex is a reproducible stimulus to endothelial-dependent coronary vasodilation while also increasing coronary sympathetic vasoconstrictor drive. The coronary endothelial function testing was performed in healthy young adult cigarette smokers (n=5) and age-matched e-cigarette users (n=8), ages 21–38 years: a) after overnight smoking/vaping abstinence; and b) immediately after smoking one Camel-filtered ciga...