Na-K ATPase / SERCA2a

Class

Lusitropic/inotropic calcium-cycling modulator

This mechanism targets two proteins that govern how calcium moves in and out of heart muscle cells during each heartbeat: the sodium-potassium ATPase (Na-K ATPase), a pump that maintains ion gradients across the cell membrane, and SERCA2a (sarco/endoplasmic reticulum calcium ATPase 2a), a pump that returns calcium to internal storage after contraction. Modulating both simultaneously is intended to address two separate problems in heart failure: weakened contraction (systolic dysfunction) and impaired relaxation (diastolic dysfunction). Partially inhibiting Na-K ATPase raises intracellular sodium, which indirectly increases the calcium available to the contractile machinery, producing a positive inotropic (contraction-enhancing) effect similar in principle to older cardiac glycoside drugs. Stimulating SERCA2a accelerates calcium removal from the cytoplasm between heartbeats, improving diastolic relaxation, a lusitropic effect that classic glycosides lack and can worsen. Together, this profile aims to strengthen contraction while also improving the heart's ability to relax and refill, a combination relevant to heart failure syndromes where both functions are compromised, including acute decompensated states requiring rapid hemodynamic support.