The Comparison Of Adenosine Triphosphate And Adenosine Dosage Which Initiate Dual Atrioventricular Nodal Physiology And Clinical Value

Atrioventricular nodal re-entry tachycardia (AVNRT) is a major sort of paroxysmal supraventricular tachycardia(PSVT). It is an effective method to apply the technique of radiofrenquency ablation (RFCA) to ablation of AVNRT. Whereas, it costs much time to identify a successful radiofrequence ablation endpoint of AVNRT because it needs numerous trials of arrhymia provocation and lacks a rapid and simple method. Adenosine triphosphate (ATP) is an endogenous nucleoside that is involved in markedly electrophysiology processes. Adenosine is active metabolite of ATP in vivo. ATP and adenosine depress the conduction of atrioventricular node(AVN) through binding the AI receptor of AVN and the effect is dosage-depended. Adenosine is more potent in fast pathway than slow pathway. Therefore, such phenomena provide hypothesis for our study. This study aims to look for an effective and simple dosage range to initiate the phenomena. It compares the dosage correlation of (he two drugs. Furthermore, this research compares the effect of ATP test between pre-ablation and after ablation. As a result, the application of this method can identify the determining of slow pathway block. So, this study can successfully initiate dual AVN physiology(DAVNP) through a simply little andprogressive dosage method. It is regarded as an identification of the endpoint of ablation of AVNRT.Object: This research looks for a rapid, simple, little and safe dosage of ATP and adenosine, which efficiently initiates the phenomena of DAVNP. Furthermore, ii compares the dosage relation of the two drugs and diagnoses AVNRT prc-opcration. It also researches whether it is feasible to apply this method to identify the ablation endpoint of AVNRT.Methods:22 patients(age 11 to 65) underwent radiofrequence ablation in our hospital during 1999 and 2001. Before the study, we underwent diagnostic elcctrophysiologic studies to determine the sort of PSVT. These patients were all typical AVNRT(slow-fast type). During sinus rhythm, ATP and adenosine injected progressively from peripheral vein until study endpoint. The initial dosage of ATP was 6mg, and the progressive dosage was 5mg. The initial dosage of adenosine was 6mg, and the progressive dosage was 3mg. Simultaneously, this study recorded a number of general data as well as cleclrophysiological data, including age, weight, antergrade and retrograde ERP of AVN, antergrade and retrograde Wenckebach's point, cycle length of tachycardia. We compared the dosage of positive results and the data in order to find correlation data to forecast positive results. We also compared the ATP and adenosine that could simultaneously initiate positive results. At last, we siudled whether it was feasible to apply this method to identify the ablation endpoint of slow pathway.ReSultS:This study showed non-correlation between drug andclcctrophysiology data. But, there were excellent linearity correlation between ATP and adenosine.CONCLUSION:1. Little dosage and progressive dosage methods of ATP can efficiently initiate DAVNP, that is a simple and rapid method to diagnose AVNRT. The initial dosage of ATP is 10mg, and the progressive is 5mg. The initial dosage of adenosine is 6mg, and the progressive is 3mg. The range of dosage is non-correlation with general data and electrophysiology data. But there were excellent linearity correlation between ATP and adenosine.2. This method can be regarded as a criterion to identify the ablation endpoint of slow pathway.