Doctors at the Maggiore Hospital in Bologna, Italy noticed that on days with high levels of air pollution, clusters of patients would visit the emergency room with symptoms of heart arrhythmia. Heart arrhythmia occurs when the electrical impulses in the heart malfunction and cause the heart to beat irregularly, causing symptoms including fluttering in the chest, chest pain, and dizziness. They suspected that these occurrences were directly related to the level of air pollution.
In a study presented at the scientific congress of the European Society of Cardiology (ESC), the doctors followed 146 patients who had received an Implantable Cardioverter Defibrillator (ICD), which is a medical device used to prevent cardiac arrest in patients at risk for life-threatening arrhythmias. The doctors also monitored levels of particulate matter, a metric for air pollution that measures the number of inhalable particles in the air.
The researchers found a significant increase in arrhythmias when particulate matter levels increased above a certain amount. When particulate matter concentrations increased by 1 μg/m3 for an entire week, there was a 2.4% higher likelihood of arrhythmias in the group they were studying. In general, they found a 1.5% increased risk of arrhythmias for each 1 μg/m3 elevation in particulate matter concentration.
As reported by Labroots, air pollution has been previously linked to the incidence of heart attacks and other major cardiovascular events. In a retrospective study, researchers found that those living in areas with a higher level of air pollution were at a higher risk for developing these severe cardiovascular complications. The World Health Organization estimates that outdoor air pollution kills 4.2 million people every year. Air pollution was also ranked as the fourth highest risk factor in mortality, after high blood pressure, tobacco use, and poor diet.
Though air pollution is sometimes unavoidable, those at high risk for arrhythmias and other heart complications can assess their risk daily by checking air pollution levels. When particulate matter concentration is high (above 35 μg/m3), the researchers recommend those at risk modify their behavior by staying inside if possible, wearing an N95 mask outside if necessary, and using an air purifier inside of the home. These simple actions could decrease the likelihood of experiencing a life-threatening arrhythmia.