Matter of the Heart


Microscopic particles in polluted air can adversely affect the heart's ability to conduct electrical signals in people with serious coronary artery disease, said researchers of Harvard University in Boston. They studied 48 patients, all of whom had coronary artery disease. Round-the-clock monitors was used to examine electrocardiograms for the conductivity change called an ST-segment depression, which indicates inadequate blood flow to the heart. Increased levels of particulate pollution (PM 2.5 and carbon) and sulphur dioxide were associated with ST -segment depression. Also, patients recovering from a heart attack had greater changes in ST segment depression on electrocardiograms compared to other participants. These findings expand the evidence that air pollution can affect heart health, either through inflaming the heart muscle or through reducing blood flow to the heart.


Down To Earth, October 2008