Effects of 2,3-butanedione monoxime on atrial-atrioventricular nodal conduction in isolated rabbit heart

Yuanna Cheng*, Kent Mowrey, Igor R. Efimov, David R. Van Wagoner, Patrick J. Tchou, Todor N. Mazgalev

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

42 Scopus citations


Introduction: 2,3-Butanedione monoxime (BDM) has been found to reversibly block cardiac contraction, without blocking electrical conduction. This study characterizes the dose-dependent effects of BDM on the conduction through the atrioventricular node (AVN) of rabbit heart. Methods and Results: Thirteen isolated atrial-AVN preparations were used in control, during and after exposure to 5, 10, and 20 mM BDM. Anterograde and retrograde pacing protocols were used to obtain the Wenckebach cycle length, effective and functional refractory periods of the AVN, index of AVN conduction delay (the area under the AVN conduction curve), as well as index of intra-atrial conduction delay between the AVN inputs. Compared to control, 5 and 10 mM BDM produced either shortening or no effect on all of the above parameters except a slight (6% and 14%, respectively) increase in the intra-atrial delay. At 20 mM, BDM produced a further increase in the intra-atrial delay (up to 50%) as well as in the retrograde AVN conduction delay (up to 16%), while the characteristics of the anterograde conduction were still improved. The effects of perfusion with BDM on these parameters were reversible after washout. Conclusions: Aside from its known effect as an electromechanical uncoupler, BDM reversibly altered some of the electrical responses of the AVN. Most of these alterations, however, did not impede but rather improved AVN conduction. Since a dose of 10 mM is sufficient to fully eliminate undesirable motion, BDM should be considered a safe and valuable tool in AVN studies in vitro requiring a mechanically quiescent preparation.

Original languageEnglish (US)
Pages (from-to)790-802
Number of pages13
JournalJournal of cardiovascular electrophysiology
Issue number7
StatePublished - 1997


  • 2,3-butanedione monoxime
  • Atrioventricular node
  • Conduction of cardiac impulse
  • Diacetyl monoxime

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)


Dive into the research topics of 'Effects of 2,3-butanedione monoxime on atrial-atrioventricular nodal conduction in isolated rabbit heart'. Together they form a unique fingerprint.

Cite this