Cardiac Sympathetic Imaging With mIBG in Heart Failure

Abstract

Cardiac sympathetic imaging with meta-iodobenzylguanidine (mIBG) is a noninvasive tool to risk stratify patients with heart failure (HF). In patients with ischemic and nonischemic cardiomyopathy, cardiac mIBG activity is a very powerful predictor of survival. Cardiac sympathetic imaging can help in understanding how sympathetic overactivity exerts its deleterious actions, which may result in better therapy and outcome for patients with HF.

Essential role of sympathetic endothelin A receptors for adverse cardiac remodeling

“…2A). To address the question of whether depleted myocardial NE stores were mediated-at least in part-by a reduced NE reuptake via the NE transporter (NET), we used the [ 124 I]-MIBG-PET method to assess cardiac NET activity in vivo (17,18,26). This method does not directly measure cardiac sympathetic activity but serves as an index for cardiac sympathetic activity.…”

“…Thus, an ET A i trial with this small HF patient cohort might be an interesting approach to test the hypothesis that patients without antiadrenergic therapy might benefit from ET A i. Moreover, imaging techniques such as [ 123 I]-MIBG uptake (17,18,26) that allow an assessment of the sympathetic nerve function in patients may serve as a tool for the selection of patients that benefit in particular from ET A i.…”

Nuclear Molecular Imaging of the Failing Heart

“…Myocardial imaging with 123 I-MIBG, the analogue of norepinephrine (NE), could visualize the activity and the innervation of adrenal sympathetic nervous system in the heart, and is widely used for evaluation of the patients with heart failure (6,15). Increased sympathetic nervous activity or denervation are seen in heart failure patients, and could be imaged with myocardial 123 I-MIBG image (16).…”

What will be the role of I-123 MIBG in improving the outcome of medically treated heart failure patients?

“…35 In addition to visual analysis of the images, a heart-to-mediastinum ratio (HMR) can be calculated as shown in Figure 2. The I-123 MIBG washout (WO) rate from the myocardium can be calculated using early and delayed images.…”