Age and anesthetic effects on murine electrocardiography

Alysia A. Chaves, Spencer J. Dech, Tomohiro Nakayama, Robert L. Hamlin, John Anthony Bauer, Cynthia A. Carnes

Research output: Contribution to journalArticlepeer-review

35 Scopus citations


Murine models offer potential insights regarding human cardiac disease, but efficient and reliable methods for phenotype evaluation are necessary. We employed non-invasive electrocardiography (ECG) in mice, investigating statistical reliability of these parameters with respect to anesthetic and animal age. Mice (C57BL/6, 8 or 48 weeks) were anesthetized by ketamine/xylazine (K/X, 80/10 mg/kg ip) or by inhalation anesthetic (halothane, HAL; sevoflurane, SEV) and 6 lead ECGs were recorded. P wave duration and QT interval was significantly prolonged with K/X compared to HAL and SEV, indicating slowed atrial and ventricular conduction. P-R interval (atrio-ventricular conduction) was significantly increased in aged mice under all anesthetics. Heart rate was inversely correlated to QT interval and P wave duration. We also detected significant age effects with respect to optimal approaches for QT interval corrections. Power analysis showed 4-fold higher number of mice/group, were required for K/X, to achieve identical statistical sensitivity. These data demonstrate the importance of anesthetic selection for relevant and reliable ECG analysis in mice and illustrate the selective influences of anesthetics and age on cardiac conductance in this species.

Original languageEnglish
Pages (from-to)2401-2412
Number of pages12
JournalLife Sciences
Issue number21
StatePublished - Apr 11 2003

Bibliographical note

Funding Information:
This work was supported in part by the National Institutes of Health (HL59791, HL63067, DK55053) and American Heart Association, National Center (0130309N).


  • Age
  • Anesthesia
  • Electrocardiography
  • Murine

ASJC Scopus subject areas

  • General Pharmacology, Toxicology and Pharmaceutics
  • General Biochemistry, Genetics and Molecular Biology


Dive into the research topics of 'Age and anesthetic effects on murine electrocardiography'. Together they form a unique fingerprint.

Cite this