E-Cigarettes May Slow Heart Rate

Exposure to e-cigarette vapor may increase blood pressure before heart rate dropped.

E-cigarettes have been perceived as a healthier alternative to tobacco cigarettes by many Americans, especially among young adults; however, there is a lack of scientific evidence that these claims are true. In fact, several studies have shown that e-cigarettes may be harmful to heart health.

Electronic nicotine delivery systems—including e-cigarettes—were observed to change heart rhythm and heart function in mice, according to a study presented at the American Heart Association’s Scientific Sessions 2017.

E-cigarettes typically include nicotine, propylene glycol (PG), and/or vegetable glycerine (VG). The study authors said these substances limit moisture loss in lotions and can be used as food additives. The effects of inhaling these substances are unknown.

In the study, the investigators analyzed the cardiovascular effects of e-cigarette vapors compared with traditional cigarettes in mice.

They discovered that exposure the both e-cigarette or cigarette smoke significantly slowed the heart rate in mice, according to the study. Additionally, exposure to an aerosol of 50:50 VG and PG was observed to extend the heart’s electrical cycle.

Notably, when heated, the authors discovered that PG and/or VG created aldehydes, acrolein, acetaldehyde, and formaldehyde, which may be dangerous to human health, according to the study. However, of these chemicals, only acrolein slowed the heart rate in mice.

The authors also found that exposure to acrolein or PG:VG aerosol was observed to spike blood pressure in mice prior to the heart rate dropping, according to the study.

These findings suggest that exposure to e-cigarette vapor may have significant cardiovascular effects, including an increased risk of atrial fibrillation and cardiovascular disease, according to the study.

The authors report that more studies are needed to determine the cardiovascular effects e-cigarettes may have in humans.

Another study—presented at the Cardiovascular Aging: New Frontiers and Old Friends meeting—found that a single exposure to e-cigarette vapor may result in impaired cardiovascular function. The authors discovered that 5 minutes of exposure to e-cigarette vapor resulted in artery narrowing by 30% within 1 hour, and the vessel’s ability to widen was also diminished.

A CDC/FDA study showed that the rate of e-cigarette use is declining among school-aged children, suggesting that prevention methods may be effective. While more information is needed about the effects of e-cigarettes on health, the CDC advises young adults to abstain from using the products.