An electronic cigarette mimics the sensations and actions experienced by tobacco smoking, but instead of breathing in smoke, the user inhales vapor. The device contains a cartridge filled with liquid, a heating element to evaporate the liquid, and a battery.

Previous studies have shown that electronic cigarettes contain fewer toxins than tobacco cigarettes. The majority of studies have not detected nitrosamines in electronic cigarettes. (tobacco-specific) Nitrosamines form part of an important group of carcinogens in tobacco products. The few that did detect nitrosamines in the devices reported levels 500 to 1,400 less than what most cigarettes contain. In order to breathe in the nitrosamines contained in one tobacco cigarette, an electronic cigarette user would need to use his/her device every day for 4 to 12 months.

E-cigarette users can choose to inhale vaporized nicotine or non-nicotine vaporized solutions. Regular tobacco smoking is associated with heart disease and death; 40% of smoking-related mortality is due to just coronary artery disease. Dr. Farsalinos and team set out to determine what acute effects electronic cigarettes might have on cardiac function.

As electronic cigarettes are marketed specifically at tobacco smokers as a healthier option, the scientists wanted to compare their results against the acute effects of tobacco cigarettes on cardiac function.

Studies had already shown that inhaling tobacco smoke produces immediate defects in my ocardial function. This probably means that healthy young regular tobacco smokers with no current symptoms may already have sustained some type of subclinical dysfunction.

The team wanted to see whether the signs detected in tobacco smokers were also present in regular electronic cigarette users.

Their study involved 42 volunteers - 20 healthy regular smokers aged 25 to 45 years and 22 regular electronic cigarette users of the same age. Both groups were tested before and after smoking one tobacco cigarette or using an electronic cigarette for seven minutes.

Dr. Farsalinos explained that they only used experience electronic cigarette users, because they tend to use the device more intensely.

Those in the electronic cigarette group had cartridges with a solution of nicotine (concentration 11mg/ml). An independent toxicology lab was used to test the solution - they found no traces of nitrosamines or polycyclic aromatic hydrocarbons.

Echocardiography, blood pressure, and heart rates were examined to determine myocardial function.