Objective: The purpose of the study was to test the dose-effect relationship of adenosine for the diagnosis of dual atrioventricular (AV) nodal physiology in patients presenting with supraventricular tachycardia. Subjects and Methods: The study population consisted of 57 patients (mean age 50 ± 14 years; 36 females, 21 males) with palpitations related to supraventricular tachycardia. Adenosine was injected as bolus during sinus rhythm at rest in order to unmask dual AV nodal physiology by a PR jump on surface ECG (defined as a sudden increase by ≧50 ms measured from the onset of the P-wave to the R-wave between two consecutive sinus beats). According to a stepwise clinical approach, adenosine was administered as bolus in incremental dosages (6 mg followed by 12 mg, if necessary up to 18 mg). Once a PR jump ≧50 ms or a high-grade AV block was noted on surface ECG, the injection was stopped at that dose. Results: A significant PR jump was noted after injection of 6 mg (n = 21, 99 ± 30 ms) or 12 mg (n = 13, 94 ± 35 ms), but not after 18 mg (n = 4, 35 ± 10 ms) adenosine. Provocation of temporary first-grade AV block (n = 13) was associated with the longest increment of PR interval, whereas high-grade AV block (n = 36) produced a significantly shorter PR jump (105 ± 35 vs. 65 ± 40 ms, p = 0.0024). Electrophysiological study and ablation were performed in 37 highly symptomatic patients. AV nodal reentrant tachycardia was diagnosed in 33 patients and orthodromic AV reentrant tachycardia in 4 patients. Conclusion: The adenosine test was characterized by a reverse dose-effect relationship as far as identification of AV nodal duality was concerned.

Keywords:
Adenosine, Atrioventricular nodal duality, Atrioventricular nodal reentrant tachycardia, Supraventricular tachycardia
This content is only available via PDF.
© 2007 S. Karger AG, Basel
2007
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.