How does digoxin exert an inotropic effect on the myocardium?

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The implementation of digoxin in the treatment of chronic heart failure stems from its capacity to exert an inotropic effect on the myocardium.Cardiac glycosides reversibly inhibit the Na⁺/K⁺-ATPase pump located in the cardiac heart muscle,leading to a net loss of potassium and a net gain in intracellular sodium concentration.This action results in activation of the sodium-calcium active transport system,which pumps sodium out of the cell and calcium into the cell.Elevated intracellular calcium concentrations result in further calcium secretion from the endoplasmic reticulum,ultimately stimulating the actin-myosin light chain reaction,resulting in myocardial contraction.Digoxin also has an inhibitory effect on the vagus nerve,leading to decreased heart rate and atrioventricular node prolongation.

How Does Digoxin Exert an Inotropic Effect on the Myocardium