Template:Digoxin mechanism
- Inhibits Na+/K+ ATPase in the myocardium[1]
- Causes increase in intracellular sodium levels
- Results in reversal of sodium-calcium exchanger
- Normally imports three extracellular sodium ions into the cardiac myocyte in exchange for one intracellular calcium being exported
- Sodium accumulates intracellularly and is exchanged for Calcium.
- Causes an increase in the intracellular calcium concentration increasing contractility
- Also a lengthening of phase 4 and phase 0 of the cardiac action potential which ultimately decreases heart rate
- Summary
- Inhibits NaK pump
- Positive inotropy
- Negative chronotropy/dromotropy
- Indirect vagal stimulator
- Inhibits NaK pump
- ↑ Gheorghiade M. et al. Digoxin in the Management of Cardiovascular Disorders. Circulation. 2004; 109: 2959-2964