Cardiac neuronal imaging with ¹²³I-meta-iodobenzylguanidine in heart failure: implications of endpoint selection and quantitative analysis on clinical decisions

Excerpt

There are a number of radiopharmaceuticals that can be used to investigate autonomic neuronal functions [1]. Among these, the norepinephrine analogue meta-iodobenzylguanidine (MIBG) labelled with ¹²³I has been widely used and validated as a marker of adrenergic neuron function [2‐4]. The first study addressing the prognostic value of ¹²³I-MIBG imaging in heart failure (HF) was that of Merlet et al. [5] in 90 patients suffering from either ischaemic or idiopathic cardiomyopathy. After publication of this study, more recent studies have indicated that patients with HF and decreased late heart-to-mediastinum (H/M) ratio or increased myocardial MIBG washout have a worse prognosis than those with normal quantitative myocardial MIBG parameters [6]. However, MIBG scintigraphy has still to reach widespread clinical application mainly because of the value of other cheaper variables such as left ventricular (LV) ejection fraction and brain natriuretic peptide (BNP) plasma levels. The possibility that the detection of mechanical dyssynchrony by innervation imaging might identify patients who would benefit from resynchronization pacing is another area of research interest [7]. …