Cardiac sympathetic upregulation is one of the neurohormonal compensation mechanisms that play an important role in the pathogenesis of chronic heart failure (CHF). In the past decades, cardiac ¹²³I-mIBG scintigraphy has been established as a feasible technique to evaluate the global and regional cardiac sympathetic innervation. Although cardiac ¹²³I-mIBG imaging has been studied in many cardiac and neurological diseases, it has extensively been studied in ischemic and non-ischemic CHF. Therefore, this review will focus on the role of ¹²³I-mIBG imaging in CHF. This non-invasive, widely available technique has been established to evaluate the prognosis in CHF. Standardization, especially among various combinations of gamma camera and collimator, is important for identifying appropriate thresholds for adequate risk stratification. Interestingly, in contrast to the linear relationship between ¹²³I-mIBG-derived parameters and overall prognosis, there seems to be a “bell-shape” curve for ¹²³I-mIBG-derived parameters in relation to ventricular arrhythmia or appropriate implantable cardioverter defibrillator (ICD) therapy in patients with ischemic CHF. In addition, there is a potential clinical role for cardiac ¹²³I-mIBG imaging in optimizing patient selection for implantation of expensive devices such as ICD and cardiac resynchronization therapy (CRT). Based on cardiac ¹²³I-mIBG data risk models and machine learning, models have been developed for appropriate risk assessment in CHF.

Purpose: A high SUV_max tumor-to-liver ratio (TLR) of ⁶⁸Ga-DOTATATE can be used to select patients with neuroendocrine tumors (NETs) for peptide receptor radionuclide therapy (PRRT). In addition, an SUV_max TLR ≥ 8.1 is associated with increased progression-free survival in NET patients treated with somatostatin analogs (SSAs). To avoid a theoretical interaction, several guidelines recommend performing PET/CT just before the monthly administration of long-acting SSAs. We aimed to investigate the effect of SSA on the SUV_max of ⁶⁸Ga-DOTATATE in patients with NET and to identify independent predictors for high SUV_max TLR. Patients and Methods: For this retrospective study, 192 ⁶⁸Ga-DOTATATE PET/CT scans of 165 patients without (n = 115) and with (n = 77) SSA (octreotide or lanreotide) in the 3 months before PET/CT were collected and reviewed. The effect of SSA on SUV_max values was analyzed by a maximum likelihood mixed model. Results: Patients with SSA had a significantly higher median SUV_max TLR than patients without SSA (4.7 [IQR], 3.1–7.7) versus 3.2 [IQR, 2.0–5.4]; P < 0.001). Multivariable logistic regression analysis showed that SSA use was an independent predictor for SUV_max TLR ≥ 8.1 (odds ratio, 2.91; 95% confidence interval, 1.26–6.72; P = 0.012). Conclusions: Our data suggest that higher SSA concentrations do not have a negative effect on ⁶⁸Ga-DOTATATE uptake in tumor lesions. In addition, we found that only SSA use was associated with SUV_max TLR ≥ 8.1. Our results are consistent with previously conducted studies and in line with the recently published guideline that suggests that the relatively recent use of SSA does not necessitate any delay in ⁶⁸Ga-DOTATATE PET/CT imaging.

Aortic valve stenosis (AVS) is an increasingly prevalent disease in our aging population. Although multiple risk factors for AVS have been elucidated, medical therapies capable of slowing down disease progression remain unavailable. Molecular imaging technologies are opening up avenues for the non-invasive assessment of disease progression, allowing the assessment of (early) medical interventions. This review will focus on the role of positron emission tomography of the aortic valve with ¹⁸F-fluorodeoxyglucose and ¹⁸F-sodium fluoride but will also shed light on novel tracers which have potential in AVS, ranging from the healthy aortic valve to end-stage valvular disease.