A new approach to characterize cardiac sodium storage by combining fluorescence photometry and magnetic resonance imaging in small animal research.

Cardiac myocyte sodium (Na) homoeostasis is pivotal in cardiac diseases and heart failure. Intracellular Na ([Na]) is an important regulator of excitation-contraction coupling and mitochondrial energetics. In addition, extracellular Na ([Na]) and its water-free storage trigger collagen cross-linking, myocardial stiffening and impaired cardiac function.