Effects of short- and long-term exposure to air pollution on myocardial perfusion imaging

Abstract Background Air pollution contributes to cardiovascular morbimortality. Cardiovascular effects assessed from non-invasive and invasive imaging were reported but never in single-photon emission computed tomography (SPECT). Objectives This study aimed to characterize relations of short and long- term air pollution exposure to myocardial perfusion imaging (MPI). Methods Patients referred to nuclear medicine department for a SPECT MPI were prospectively and consecutively enrolled between 2017 and 2020. Summed stress score (SSS) and myocardial ischemia were assessed. Short-term (7-day daily averages before the SPECT; a potential lag effect was studied in addition) and long-term average exposure (yearly average) to PM2.5, PM10, and NO2 were characterized via a 10 meter resolution air pollutant-dispersion model and air quality monitoring system measurements. Associations between exposures and myocardial ischemia and SSS were assessed through multivariable regressions. Results In total, 1,585 participants were included (mean age 67.7 ± 11.6 years old, 63.3% male); 148 (9.3%) presented a severe myocardial ischemia (SSS≥8) and 339 (21.4%) presented a mild ischemia (SSS ≥4). In adjusted model, risk for left ventricle ischemia ≥10% was increased by 34% [95% confidence interval (95% CI): 3-75; p = 0.031] for each increase by 3.3 µg/m3 in PM2.5 long-term exposure. This risk of obtaining a SSS ≥4 was increased by 29% (95%CI: 0-67; p = 0.048) for each increase by 15.2 µg/m3 in NO2 short term exposure. When we considered daily exposure levels, effect estimates were highest on the second and fourth days before examination for all air pollutants. Conclusion This study highlights a relationship of short- and long-term air pollution exposure to MPI. Long term exposure was in relation to severe ischemia and short term with lag effect to mild ischemia. Pic of pollution the days before SPECT could be influence result particularly in mild ischemia due to acute endothelial dysfunction.