New research presented at the European Society of Cardiology (ESC) has shown that potentially deadly arrhythmias are more common on days when there is more pollution in the air.
The study, which took place in Italy, followed 146 patients between 2013 and 2017. The patients included in the study had implantable cardioverter defibrillators (ICDs), which could be used to track arrhythmias and the delivery of therapies by the device. The researchers also monitored levels of pollution each day during the study, including PM10, PM2.5, carbon monoxide (CO), nitrogen dioxide (NO2), and ozone (O3). Pollution exposures of specific patients were determined using their home addresses. Using the pollution data in combination with the arrhythmia and therapy information from the ICDs, the researchers checked for correlations between the daily levels of air pollution and the occurrence of arrhythmias.
They found that there were significant correlations between arrhythmias and both PM2.5 and PM10 concentrations. For every 1 μg/m3 rise in PM2.5 concentrations per week compared to average, there was a 2.4% higher risk of arrhythmias. For the same rise in PM10 concentrations, there was a 2.1% higher risk.
One of the study’s authors noted that PM2.5 and PM10, which describe particulate matter of different sizes, may cause inflammation of the heart that triggers arrhythmias. Particulate pollution of these sizes can come from many sources, including cars and industrial applications. Notably, wildfire smoke is a significant source of inhalable particulate matter, including PM10 and PM2.5. As climate change increases the incidence of major wildfires in the American West, cardiac conditions including arrhythmias may be more likely to occur. On days with high pollution levels, including days with high levels of wildfire smoke, it is advisable for anyone with a history of heart disease to avoid exposure if possible.