13.01.8 Adenosine

Adenosine is a naturally occurring substance that has receptor medicated effects. It is produced in ischemia, and slows the heart rate. On the heart, adenosine acts at A1 receptors to slow sinus node activity and conduction through the atrioventricular node (Figure 13.6).

Figure 13.6 Mechanism of action of adenosine on heart (Copyright QUT, Sheila Doggrell)

Adenosine can also be used clinically to slow heart rate. Adenosine has a short duration of action. The short duration limits the used of adenosine to the emergency situation for acute treatment of supraventricular arrhythmias. In an emergency, adenosine is used intravenously, for the acute treatment of supraventricular (atrial) arrhythmias, where its rapid onset of action is a major advantage.