Effect of dexmedetomidine on conduction between the sinus node and atrioventricular node: A cardiac electrophysiologic study

Abstract

　We conducted a cardiac electrophysiologic study in a patient with suspected complete atrioventricular block caused by dexmedetomidine (DEX) to evaluate the effect of DEX treatment on sinus function and atrioventricular conduction. DEX treatment led to a decrease in the sinus node function and atrioventricular conduction in a dose-dependent manner and prolonged the atrio-His interval. In this case, complete atrioventricular block may have possibly developed by the complex participations which were a restraint effect to sinus node and atrioventricular conduction depending on DEX dose, interaction of other drugs including fentanyl and the patient characteristics.

　It is difficult to conclude that the use of DEX induced complete atrioventricular block. In addition, the combination of drugs likely to induce complete atrioventricular block is currently not known. When advanced atrioventricular block develops concurrently with DEX use, the administration of DEX must be terminated, and atropine should be administered.