Radionuclide Image-Guided Repair of the Heart

As therapeutic approaches have evolved from exogenous bone marrow cell delivery to pharmacological stimulation of endogenous repair, so too has imaging of cardiac repair made significant strides forward. Evaluation of functional outcome remains a staple of noninvasive clinical imaging, which can robustly quantify contractile function, perfusion, and tissue viability. Direct labeling of cells or other novel therapeutics visualizes the whole-body distribution and pharmacokinetics of the therapeutic agent, providing insights into retention, targeting, and drug-tissue interactions. And finally, targeted molecular imaging agents are emerging that may be specifically coupled to drugs targeting the same pathway. This approach enables interrogation of temporal and spatial changes at the molecular level underlying tissue degeneration and regeneration, which facilitates accurate patient selection and timing for therapeutic intervention, as exemplified by recent efforts focusing on the role of inflammation in cardiac repair. The concept of image-guided repair carves out an important and evolving niche for molecular imaging in cardiovascular medicine, with the potential not only to predict outcomes but also to improve patient stratification and progress toward personalized reparative therapy.