High-grade AV Block Research Articles

Differences in Chronotropic and Dromotropic Responses of the SA and AV Nodes to Adenosine and Acetylcholine

It is well known that adenosine produces a deceleration of sinus rate though not so prominent while a high grade AV block is seen in the guinea-pig. In the dog the sinus rate is so considerably retarded by adenosine that the action upon the AV conduction is not appreciated on rough examination (Drury and Szent-Gyorgyi 1929) (1). In the present study, selective perfusion systems of the sinus and AV node arteries were arranged (2). The double perfusion method has been described in a previous paper (3). Effects of adenodine on the AV conductivity in comparison with those on the automaticity of the SA or AV node were examined.

Differences in chronotropic and dromotropic responses of the SA and AV nodes to adenosine and acetylcholine.

It is well known that adenosine produces a deceleration of sinus rate though not so prominent while a high grade AV block is seen in the guinea-pig. In the dog the sinus rate is so considerably retarded by adenosine that the action upon the AV conduction is not appreciated on rough examination (Drury and Szent-Gyorgyi 1929) (1). In the present study, selective perfusion systems of the sinus and AV node arteries were arranged (2). The double perfusion method has been described in a previous paper (3). Effects of adenodine on the AV conductivity in comparison with those on the automaticity of the SA or AV node were examined.