RV glucose metabolism changes associated with RV function
medwireNews: The rate of myocardium glucose utilisation (rMGU) in the right ventricle (RV) correlates with its function and could be used to monitor treatment effects in patients with pulmonary arterial hypertension (PAH), findings indicate.
As assessed by 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), the RV rMGU was significantly higher for the 27 treatment-naïve idiopathic PAH patients than for the 21 healthy controls, at 0.094 versus 0.010 μmol/g per min.
But the left ventricular rMGU did not vary significantly between patients and controls, the researchers report in the European Heart Journal - Cardiovascular Imaging.
They found a significant positive correlation between RV rMGU and systolic, diastolic and mean pulmonary artery pressure, pulmonary vascular resistance, RV Tei index and right atrial area, while RV rMGU correlated negatively with RV ejection fraction and tricuspid annular plane systolic excursion.
Six of a subgroup of 14 patients who underwent FDG-PET after 6 months of treatment demonstrated a decrease in RV rMGU compared with baseline. These patients, but not the eight with an increased RV rMGU, also achieved a significant increase in RV ejection fraction and 6-min walk distance (6MWD) as well as a significant reduction in RV Tei index.
And the change from baseline in RV rMGU across all 14 patients showed a significant negative correlation with the change in 6MWD and a significant positive correlation with the change in RV Tei index.
These findings suggest “a reduction in glucose metabolism in the RV and [indicate] an improvement in the exercise capacity of these patients, possibly, related to a better RV function”, say Wei Fang (Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing) and co-workers. However, the association between the changes in RV rMGU and RV ejection fraction was not significant.
Noting that changes in 6MWD and RV Tei index are associated with PAH outcomes, the study authors suggest that the evaluation of RV glucose metabolism could help in evaluating right heart function. And they speculate that in idiopathic PAH patients, reductions in RV rMGU may be associated with improved outcomes.
medwireNews is an independent medical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2015