Table 1. Comparison between regadenoson and adenosine.

 Source: [10]

AV: Atrioventricular; HR: Heart rate

*Duration of action is defined as the duration of circulatory flow maintained >2.5 times of the baseline

 

Parameters	Regadenoson	Adenosine
Potency	10 times more potent than adenosine	Less potent
Receptor selectivity	Selective A2a adenosine receptor agonist	Nonselective agonist
Dose	400 ug as a single dose	140 ug/kg/min
Duration of infusion	10 seconds bolus	4 – 6 min
Radiotracer injection	30s after bolus	Third minute of infusion
Time to peak plasma concentration (Tmax )	33s	30s
Metabolism	No hepatic metabolism	Deaminated to inosine by adenosine deaminase
Excretion	57% appears unchanged in urine	Cellular uptake
Half-life	1st phase: 2 – 4 min 2nd phase: 30 min 3rd phase: 2 h	< 10 s
Duration of action	2.3 min*	6 s*
Coronary blood flow	Increased to >2 times baseline in 30 s and decreased to < 2 times baseline in 10 min	Maximum response at 2 – 3 min after infusion onset; return to baseline within 1 – 2 min following cessation of infusion
Coronary hyperemia	2 – 5 min longer than adenosine	Lesser effect
Heart rate	Faster and greater peak increase in HR	Less fast and lesser peak in HR
Adverse effects	Less hypotension, AV blocks, bronchoconstriction	hypotension, AV blocks, bronchoconstriction