in addition , to study the possible reversal of drug effects by sympathetic stimulation , av node conduction and tachycardia induction were reassessed during isoproterenol infusion ( 1 to 3 micrograms/min ) , a dose calculated to increase the rest heart rate by 25 +/- 10 % .
C0039231
tachycardia
C0022245
isoproterenol