Ambient air pollution and cardiac arrhythmias in patients with implantable defibrillators.

Background: Previous studies of ambient air pollution and ventricular tachyarrhythmias in patients with implantable cardioverter defibrillators have yielded mixed results. Methods: We examined this relationship in a study of 518 patients with 6287 tachyarrhythmic event-days over a 10-year period in Atlanta, Georgia. The air quality data included daily measurements of PM10,, ozone, nitrogen dioxide, carbon monoxide, and sulfur dioxide for the entire study period, as well as speciated measurements of PM2.5 mass and oxygenated hydrocarbons for the final 4 years of the study. Our primary analyses utilized generalized estimating equations, controlling for long-term time trends and meteorologic conditions as well as residual correlation within subjects. Results: Our primary modeling approach found no association; additional sensitivity analyses and alternative analytic approaches supported those findings. The most suggestive positive findings were for coarse particles. Conclusions: The present study constitutes the largest study to date of ambient air pollution and tachyarrhythmic events in patients with implantable cardioverter defibrillators. Other than the suggestive findings for coarse particles, the study provides little evidence of an association between ambient air quality levels and tachyarrhythmic events.