Short- and long-term metabolic exposure data as predicators of coronary microvascular dysfunction in a positron emission tomography myocardial perfusion imaging (PET-MPI) cohort with near concurrent angiography.

BACKGROUND: Coronary microvascular disease (CMD) is defined by impaired myocardial stress flow reactivity and is associated with worse cardiovascular outcomes. Studying CMD is complicated by the overlap of its risk factors and patient-important cardiovascular sequelae with those of epicardial atherosclerotic disease. Published studies have not yet used longitudinal data to investigate the time dependencies of dynamic processes like obesity in their effects on microvascular health.

METHODS AND RESULTS: In a mixed-sex cohort of 85 patients for whom epicardial obstruction was angiographically excluded, a multivariate model was developed to measure strengths of association between repeated-measurement metabolic data and microvascular stress flow reactivity as assessed by position emission tomography myocardial perfusion imaging (PET-MPI). Body mass index (BMI) and the diagnosis of insulin-dependent diabetes mellitus (DM) were associated with CMD on clinically meaningful scales when analysing all metabolic data collected in the year prior to stress PET-MPI (β [95% CI]: -0.019 [-0.033, -0.0051], p = 0.0072; -0.33 [-0.65, -0.0026], p = 0.048). Parallel modelling using single-time-point metabolomics data generated comparable results, suggesting that simplified assessments may be used as valid surrogates for repeated-measurement data in this setting.