Association of 24-Hour Air Pollution Exposure on Myocardial Blood Flow: A Quantitative Stress Cardiac Magnetic Resonance Study

Presenting Author(s)

• 

  Ming Yen Ng, MD, FSCMR

  Clinical Associate Professor
  The University of Hong Kong
  Hong Kong, China (People's Republic)

Primary Author(s)

• 

  Ming-Yen Ng, BMBS FRCR FSCMR

  Clinical Associate Professor
  The University of Hong Kong
  Hong Kong, Hong Kong

Co-Author(s)

• RT

  Romelie Tuplano, MD

  MD
  The University of Hong Kong, Hong Kong

Co-Author(s)

• KL

  Kwan Ho Gordon Leung

  BEng
  The University of Hong Kong, Hong Kong
• HW

  Haonan Wang, PhD

  Lead Cardiac MR Scientist
  GE HealthCare
  Waukesha, Wisconsin, United States
• EW

  Eric Yuk Fai Wan

  Assistant Professor
  The University of Hong Kong, Hong Kong
• KW

  Konrad Werys, PhD

  University of Oxford Centre for Clinical Magnetic Resonance Research, United Kingdom
• RS

  Randall Stafford

  PhD
  Circle Cardiovascular Imaging Inc., Canada
• 

  Martin A. Janich, PhD

  Director, Cardiac MRI
  GE HealthCare
  Munich, Bayern, Germany
• AY

  Andrew Yan, MD

  MD
  St. Michael's Hospital
  Toronto, Ontario, Canada
• 

  Vanessa M. Ferreira, MD, PhD, FSCMR

  Professor of Cardiovascular Medicine
  University of Oxford
  Oxford, England, United Kingdom

Background: Air pollution exposure is a significant risk factor for cardiovascular events. Air pollution’s effects on myocardial blood flow (MBF) have not been investigated. This study aims to assess the association of preceding 24-hour air pollution exposure on MBF using cardiac magnetic resonance (CMR).

Methods: Cross-sectional study of patients who underwent quantitative stress CMR from 1st April 2021 and 30th October 2024. Air pollution indices within 24 hours before the CMR scan for each patient was acquired. Multivariable linear regression, adjusted for clinical and CMR characteristics, was used to determine the effect of air pollution on stress MBF, rest MBF, and myocardial perfusion reserve (MPR) as the primary outcomes and other CMR parameters (secondary outcome).

Results: 556 patients were included (mean age 63.2 ± 12.3 years, 60% male). Ozone (O3), particulate matter (PM) with aerodynamic diameter ≤2.5µm (PM2.5) and PM with aerodynamic diameter ≤10µm (PM10), after adjustment for significant covariates (i.e. clinical, medication, CMR variables), showed significant association with stress MBF (p < 0.001, 0.001 and < 0.001, respectively). O3 showed significant association with rest MBF (p=0.011) after adjustment. For every 1 ug/m3 higher in O3, PM2.5 and PM10, the stress MBF decreased by 0.003 ml/g/min, 0.010 ml/g/min, and 0.008 ml/g/min respectively. For every 1 ug/m3 higher in O3, rest MBF decreased by 0.001 ml/g/min. No association between the air pollution indices and conventional CMR parameters was demonstrated.

Conclusion: Higher ambient PM2.5, PM10, O3 levels within the preceding 24 hours were associated with significant decrease in MBF using quantitative stress CMR.

Summary of the study design, results and discussion.