Flourine-18 Fluoro L-Dihydroxyphenylalanine (F-18 FDOPA) PET-CT in evaluation of cardiac sympathetic innervation in Heart Failure patients

648 Introduction: Cardiac sympathetic imaging is used in heart failure (HF) patients for prognostication and assessment of response to medical treatment, in selection of patients for devices, in drug-induced cardiotoxicity and in heart transplant patients. In this pilot study we tried to find whether F-18 FDOPA can be used in the evaluation of cardiac sympathetic innervation in HF patients. Methods: Fourteen patients with clinical diagnosis of HF (11 males, 3 females; mean age 44 ± 11 years; 9 NYHA class II & 5 class III) underwent F-18 FDOPA PET/CT study. They were asked to have a low-protein breakfast, and adequately hydrated on the day of the F-18 FDOPA study. A dose of 111-185 MBq (3-5 mCi) of F-18 FDOPA was injected intravenously and images were acquired after 45 minutes. From PET/CT images, myocardium to mediastinal vessel (MMR) ratio was calculated in each patient. Standard circular regions of interest (ROIs) were placed on entire myocardium, separately on inter-ventricular septum (IVS), apex, anterior, inferior and lateral left ventricular wall. Region of interest with same pixel was made on mediastinal vessel. The global and regional MMR derived in patient group was compared with the nineteen age matched controls who had undergone 18F- FDOPA PET/CT for indications other than HF and had no history of coronary artery disease or coronary risk factors. Results: In patient group, the mean regional MMR was 1.33 ± 0.26 in septum, 1.26 ± 0.31 in lateral wall, 1.12 ± 0.19 in anterior wall, 1.26 ± 0.29 in inferior wall and 1.09 ± 0.20 in apex which were significantly reduced compared to the controls who had the mean regional MMR of 1.94 ± 0.15 in septum, 1.70 ± 0.14 in lateral wall, 1.83 ± 0.14 in anterior wall, 1.95 ± 0.13 in inferior wall and 1.73 ± 0.13 in apex (p< 0.05) Also, the mean global MMR of the patient group was reduced as compared to control group (1.46 ± 0.30 vs 2.02 ±0.14; p < 0.05). Conclusions: The results of the study suggest that F18-FDOPA can be used in assessment of cardiac sympathetic innervation in HF patients. The validation of these results in a larger patient population may provide a platform for the use of easily available F-18 labeled tracer in assessment of cardiac sympathetic innervation.