Imaging Targets to Visualize the Cardiac Immune Landscape in Heart Failure

Abstract

Heart failure involves a complex interplay between diverse populations of immune cells that dynamically shift across the natural history of disease. Within this context, the character of the immune response is a key determinant of clinical outcomes. Recent technological advances in single-cell transcriptomic, spatial, and proteomic technologies have fueled an explosion of new and clinically relevant insights into distinct immune cell populations that reside within the diseased heart including potential targets for molecular imaging and therapy. In this review, we will discuss the immune cell types and their respective functions with respect to myocardial infarction remodeling, dilated cardiomyopathy, and heart failure with preserved ejection fraction. In addition, we give a brief overview regarding myocarditis and cardiac sarcoidosis as inflammatory heart failure etiologies. We will highlight markers and cell populations as targets for molecular imaging to visualize inflammation and tissue healing and discuss clinical implications including the development and implementation of precision medicine approaches.

Keywords: heart failure; immune system; inflammation; interleukin; molecular imaging.

Figure 1:. Central illustration

CT= computer tomography, DCM= dilated cardiomyopathy, HFpEF= heart failure with preserved ejection fraction, MRI= magnetic resonance imaging, PET= positron emission tomography

Figure 2:. Molecular imaging opportunities of different leukocyte subsets

Innate immune effector cells (top panel) and adaptive immune effectors (bottom panel). Some markers are only expressed in celltype subsets and some exhibit conflicting data. FDG= F-Deoxyglucose, MET= methionine, MØ= macrophage, MR= mannose receptor, NE= neutrophil elastase, PFC= perfluorocarbon, TSPO= Mitochondrial translocator protein