Prognostic role of PET/MRI hybrid imaging in patients with pulmonary arterial hypertension

ObjectiveRight ventricular (RV) function is a major determinant of survival in patients with pulmonary arterial hypertension (PAH). Metabolic alterations may precede haemodynamic and clinical deterioration. Increased RV fluorodeoxyglucose (FDG) uptake in positron emission tomography (PET) was recently associated with progressive RV dysfunction in MRI, but the prognostic value of their combination has not been established.MethodsTwenty-six clinically stable patients with PAH (49.9±15.2 years) and 12 healthy subjects (control group, 44.7±13.5 years) had simultaneous PET/MRI scans. FDG uptake was quantified as mean standardised uptake value (SUV) for both left ventricle (LV) and RV. Mean follow-up time of this study was 14.2±7.3 months and the clinical end point was defined as death or clinical deterioration.ResultsMedian SUVRV/SUVLV ratio was 1.02 (IQR 0.42–1.21) in PAH group and 0.16 (0.13–0.25) in controls, p