1991 Volume 51 Issue 3 Pages 249-260
To prevent side effects of adenosine triphosphate (ATP) in terminating paroxysmal supraventricular tachycardia (PSVT), we studied the effects of ATP on the cardiac conduction system and PSVT in 32 patients using dipyridamole (0.1 or 0.2 mg/kg) as a premedication agent. Increasing boluses of ATP (0.025, 0.05, 0.1, 0.2, 0.3, 0.4 and 0.5 mg/kg) were injected during sinus rhythm or PSVT. All PSVTs, including those at the AV node in a reentrant circuit, could be terminated by ATP. The dose with no premedication was 0.17±0.08 mg/kg ; with 0.1 mg/kg dipyridamole, it was 0.08±0.05 mg/kg ; and with 0.2 mg/kg dipyridamole, it was 0.04±0.01 mg/kg (p<0.01) . The maximum AA-interval during sinus rhythm was observed significantly earlier than the PSVT termination point, so maximum automaticity recovery time after termination by ATP alone, or with 0.1 mg/kg of dipyridamole was less than two seconds. Except for premedication with 0.2 mg/kg of dipyridamole, terminating PSVT doses were significantly smaller than the AV blocking doses during sinus rhythm. Noncardiac side effects, such as flush and dyspnea, were observed in all patients after ATP injection without premedication, but disappeared in two cases and were less in all the other patients in the presence of dipyridamole. No side effect required treatment. Thus, an appropriate combination of ATP-dipyridamole for PSVT termination, to avoid long cardiac arrest due to long automaticity recovery time, and AV block after termination ; and to reduce adverse effects is considered to be 0.1 mg/kg. We conclude that the ATP-dipyridamole (0.1 mg/kg) combination can be used effectively and safely to terminate PSVT.
