Evidence of vaping’s harmful effects on blood vessels and the left ventricle of heart

A new study by researchers at the USC Viterbi School of Engineering, in collaboration with the Keck School of Medicine of USC, the Huntington Medical Research Institutes (HMRI) and UC Irvine, highlights the harmful effects of both electronic and standard cigarettes on cardiovascular health. In short, the researchers found that electronic cigarettes harm blood vessels while standard cigarettes impair the heart.

The study published in the Journal of the American Heart Association (JAHA) was led by Rashid Alavi, during his time as a mechanical engineering PhD student in the lab of Niema Pahlevan, the Gordon S. Marshall Early Career Chair in Engineering at USC and Fellow of the American Heart Association (FAHA), Pahlevan is a leading specialist in flow physics for application in medical diagnostics and treatment, and is recognized as an innovator in non-invasive measuring techniques to gain insights into heart health.

Titled “Adverse Cardiovascular Effects of Nicotine Delivered by Chronic Electronic Cigarettes or Standard Cigarettes Captured by Cardiovascular Intrinsic Frequencies,” the study applies an innovative fluid dynamics-based analysis technique to measure the impact of nicotine exposure via e-cigarette vapor and traditional cigarette vapor.  Although the study was performed on animal models,  it can also be applied to humans, as has been done in other applications including heart failure. For humans, one can use smartphone cameras to identify abnormalities in cardiovascular function.

Pahlevan explains how the process works. “For human applications, the smartphone camera captures images of the neck skin. Then an algorithm extracts vessel wall dilation from the skin vibrations recorded in the images. This dilation waveform mirrors the pressure waveform in large arteries, such as the carotid where wall viscoelasticity is minimal.”

Results: The results reveal that nicotine-containing electronic cigarettes negatively impact vascular function and left ventricle-arterial coupling. Traditional cigarettes were also found to significantly impair left ventricle contractile function. These findings demonstrate potential long-term consequences for cardiovascular health.

“Vaping with nicotine is causing accelerated aging of the vascular system,” said Pahlevan.

Impact: While electronic cigarettes with nicotine have gained popularity as a potential aid for quitting traditional smoking, their impact on cardiovascular health remained poorly understood – until now.

“People have this idea that e-cigarettes are much better than traditional cigarettes, so they quit traditional smoking and try e-cigarettes with nicotine. However, e-cigarettes with nicotine have so many adverse effects, so they need to be carefully considered,” said Pahlevan.

“The goal of this study was to raise awareness about vaping and its long-term effects on the cardiovascular system,” said Alavi, whose thesis was recognized for the top-4 thesis in the USC Viterbi Best PhD Dissertation Award and who is now the James Boswell Postdoctoral Fellow at Caltech and HMRI. “When the vessels become impaired, this will eventually impact the heart. We want to help people to make informed decisions about whether to use a substance or not, ” Alavi added.

A smartphone tool, adds Alavi, can also be used in the final application by people who vape to allow them to assess if they are at-risk.

The intrinsic frequency method which is a new fluid dynamics-based analysis technique 'is clearly very sensitive to capture abnormalities in the cardiovascular system, even more than some standard hemodynamic measures. In addition, it is exciting that this technique can be applied to cell-phone applications to assess the heart’s function,” said Dr. Robert Kloner, Chief Scientific Officer at HMRI, and Professor of Medicine (clinical scholar) at the Keck School of Medicine of USC.

This approach holds significant potential for human applications. By developing a new, cost-effective method for detecting cardiovascular damage using only carotid pressure waveform (neck pulse) measurements, the study paves the way for faster, easier and more widespread testing.

The next step is to test the tool in human clinical trials.

Full list of authors:
Rashid Alavi , PhD; Department of Aerospace and Mechanical Engineering, University of Southern California,
Wangde Dai, MD; Division of Cardiovascular Medicine, Keck School of Medicine, University of Southern California; and Cardiovascular Research, Huntington Medical Research Institutes, Pasadena, CA
Sohrab P. Mazandarani, MA; Division of Cardiovascular Medicine, Keck School of Medicine of University of Southern California,
Rebecca J. Arechavala , PhD; Department of Environmental and Occupational Health, College of Health Sciences, University of California, Irvine, CA
David A. Herman , PhD; Department of Environmental and Occupational Health, College of Health Sciences, University of California, Irvine, CA
Michael T. Kleinman, PhD; Department of Environmental and Occupational Health, College of Health Sciences, University of California, Irvine, CA
Robert A. Kloner , MD, PhD; Division of Cardiovascular Medicine, Keck School of Medicine, University of Southern California; and Cardiovascular Research, Huntington Medical Research Institutes, Pasadena, CA
Niema M. Pahlevan , PhD: Department of Aerospace and Mechanical Engineering, University of Southern California; and Division of Cardiovascular Medicine, Keck School of Medicine University of Southern California; and Cardiovascular Research, Huntington Medical Research Institutes, Pasadena, CA

Disclosures
N.M. Pahlevan holds equity in Ventric Health (Avicena LLC) and has a consulting agreement with Ventric Health (Avicena LLC).