Abstract 13349: The Effect of Chronic Standard Cigarette Smoke Exposure Compared to Chronic Electronic Cigarette Exposure With or Without Nicotine on Blood Pressure

Abstract

Background: While the acute exposure to electronic cigarette (e-C) vapor has been associated with an increase in blood pressure, the chronic effect of e-C vapor on blood pressure compared to standard cigarette smoke has not been extensively studied. We determined the effect of chronic e-C exposure versus standard cigarette smoke on blood pressure and other cardiac functional measures. Methods: Sprague Dawley rats (both sexes) were randomly exposed to air (n=34), e-C with nicotine (e-Cn; n=30), e-C without nicotine (e-C; n= 28) or standard cigarette smoke (SCS; n=27) for 12 weeks. After 12 weeks of exposure hemodynamics were determined by Millar catheter, echocardiography, and thermodilution catheter, a few days after their last exposure. Results: As shown in the Table, SCS was associated with higher systolic, diastolic and mean blood pressures and peak LV systolic pressure compared to air or e-Cn or e-C groups. Neither fractional shortening or cardiac output differed among the groups. dp/dt min, a measure of diastolic LV function, was lowest in the e-C group. Tau, a measure of LV relaxation was worse in this group as well. Conclusions: Standard cigarette smoke exposure was associated with an increase in blood pressure when blood pressure was tested at 12 weeks. Neither electronic cigarette smoke with or without nicotine caused an increase in blood pressure compared to air. However, e-C was associated with worse diastolic function. Standard cigarettes may be associated with a greater sympathetic surge causing elevated blood pressure compared to electronic cigarettes.