A latest University of Washington study has found exposure to high levels of traffic-related air pollution causes changes in the right ventricle of the heart. The finding adds to the existing evidence that has established a relationship between air pollution exposure and heart disease.

"Although the link between traffic-related air pollution and left ventricular hypertrophy, heart failure, and cardiovascular death is established, the effects of traffic-related air pollution on the right ventricle have not been well studied," lead author Peter Leary, MD, MS, from Medical Center in Seattle, said in a press release.

Leary said that they used nitrogen dioxide to mimic traffic-related air pollution. The researchers found that increased exposure was linked to greater right ventricular mass and larger right ventricular end-diastolic volume. Greater right ventricular mass increases the risk for heart failure and cardiovascular death.

For the study, the researchers exposed 3,896 participants, who did not suffer from any cardiovascular disease, to outdoor oxides of nitrogen at their homes for a year before taking MRI scans. The researchers found that increased exposure to nitrogen dioxide led to an approximately 1.0 g (5 percent) increase in right ventricular mass and a 4.1 mL (3 percent) rise in right ventricular end-diastolic volume.

"The morphologic changes in the right ventricle of the heart that we found with increased exposure to nitrogen dioxide add to the body of evidence supporting a connection between traffic-related air pollution and cardiovascular disease," said Leary. "The many adverse effects of air pollution on human health support continued efforts to reduce this burden."

The findings were published online in the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine.