Noradrenergic uptake in the liver on 123 I‐ m IBG imaging: Influence of heart failure and diabetes

Background and Aim Imaging noradrenergic uptake in the liver with norepinephrine analog 123 I‐meta‐iodobenzylguanidine ( m IBG) was explored in normal controls and patients with heart failure (HF). Methods A total of 961 HF (343 with diabetes mellitus [DM]) and 94 control subjects underwent anterior planar m IBG images including upper abdomen at 15 min (early) and 3 h 50 min (late) post‐injection. Decay‐corrected liver activity normalized to injected activity and body surface area (counts/pixel [cpp]/MBq/m 2 ) was compared in three groups: HF with DM; HF without DM; and controls. Associations with plasma norepinephrine, liver function tests, and level of cardiac innervation were explored. Results In controls, liver m IBG activity decreased over time (early: 2.78 vs late: 2.43 cpp/MBq/m 2 , P  < 0.0001); in HF subjects, activity increased during this interval (HF without DM: 2.85 vs 2.93 [ P  = 0.005]; HF with DM: 2.37 vs 2.43 [ P  = 0.054]). Early liver activity was lower in HF with DM subjects than in the other groups ( P  < 0.001); late liver activity was higher in HF without DM than in the other two groups ( P  < 0.01). Subjects with elevated plasma norepinephrine (> 520 pg/mL) or ≥ 1 abnormal liver function test had lower early and late liver activity. In subjects with preserved cardiac m IBG uptake, HF subjects had higher and control subjects lower liver activity than comparable subjects with decreased cardiac innervation. Conclusions In HF subjects, liver m IBG activity increased over time, reversing the normal washout pattern, suggesting a compensatory change in sympathetic nerve function. DM, abnormal liver function tests, and decreased cardiac innervation were associated with decreased liver m IBG uptake in HF.