Metabolic effects of pulmonary obstruction on myocardial functioning: a pilot study using multiple time-point F-18-FDG-PET imaging

摘要

RationaleThe aim of this study was to evaluate fluorine-18 fluorodeoxyglucose (F-18-FDG) uptake in the right ventricle (RV) of patients with chronic obstructive pulmonary disease (COPD) and to characterize the variability of F-18-FDG uptake in the RV at different time points following radiotracer administration using PET/computerized tomography (CT). Impaired RV systolic function, RV hypertrophy, and RV dilation are associated with increases in mean pulmonary arterial pressure in patients with COPD. Metabolic changes in the RV using F-18-FDG-PET images 2 and 3h after tracer injection have not yet been investigated.MethodsTwenty-five patients with clinical suspicion of lung cancer underwent F-18-FDG-PET/CT imaging at 1, 2, and 3h after tracer injection. Standardized uptake values (SUVs) and volumes of RV were recorded from transaxial sections to quantify the metabolic activity.ResultsThe SUV of RV was higher in patients with COPD stages 1-3 as compared with that in patients with COPD stage 0. RV SUV was inversely correlated with FEV1/FVC pack-years of smoking at 1h after F-18-FDG injection. In the majority of patients, F-18-FDG activity in RV decreased over time. There was no significant difference in the RV myocardial free wall and chamber volume on the basis of COPD status.ConclusionThe severity of lung obstruction and pack-years of smoking correlate with the level of F-18-FDG uptake in the RV myocardium, suggesting that there may be metabolic changes in the RV associated with lung obstruction that can be detected noninvasively using F-18-FDG-PET/CT. Multiple time-point images of the RV did not yield any additional value in this study.