It has been known for several years now that exposure to heavy road traffic can trigger heart attacks and that particulate air pollution increases the risk of heart attack and cardiac death. Now scientists are beginning to discover the mechanisms by which pollutants damage the heart.
The Journal of the American Heart Association reports that pollutants can interfere with the heart’s ability to conduct electrical signals in people with coronary artery disease.
Researchers monitored patients to look for a conductivity change called an “ST-segment depression,” which may be a sign of inadequate blood flow or inflamed heart muscle.
“We found that an elevation in fine particles, from non-traffic as well as traffic sources, and black carbon, a marker for traffic, predicted ST-segment depression,” said lead researcher Diane R. Gold, M.D., M.P.H. “Effects were greatest within the first month after hospitalization, and for patients who were hospitalized for a heart attack or had diabetes.”
Gold is not very surprised by her findings. “When coal sales were banned in Dublin, Ireland, and black smoke concentrations declined by 70 percent within the next 72 months, cardiovascular deaths fell by 10 percent,” she pointed out.
What surprises me is that patients in this study were all breathing air that would be considered healthy by National Air Quality standards! If “healthy” air can cause the heart to malfunction in a short period of time, just imagine the cumulative, long-term effects of breathing heavily polluted air.
The American Heart Association recommends that some heart patients avoid driving in heavy traffic for a while after a hospital stay. Heavy traffic can be stressful, and it also produces harmful air pollution.
Scientists are still trying to explain exactly how tiny particles damage the heart. Gold says, “Further research is needed to evaluate whether the pollution-related ST-segment depression that we see is related to increased heart muscle inflammation, reduced oxygen flow, oxidative stress, or increased risk of arrhythmias.”
Keep your heart, lungs, and immune system healthy by investing in an air purifier to eliminate air pollution. Remember, even so-called “healthy” levels of air pollution can damage your body.