Faculty Collaboration Database

Halothane, enflurane and isoflurane on abnormal automaticity and triggered rhythmic activity of Purkinje fibers from 24-hour-old infarcted canine hearts. Anesthesiology 1991 Nov;75(5):847-53

Date

11/01/1991

Pubmed ID

1952209

DOI

10.1097/00000542-199111000-00017

Scopus ID

2-s2.0-0025935545 (requires institutional sign-in at Scopus site)   9 Citations

Abstract

The effects of inhalation anesthetics halothane, enflurane, and isoflurane on spontaneous impulse initiation (automaticity) and triggered sustained rhythmic activity were examined in Purkinje fibers derived from normal (n = 38) and 24-h-old infarcted canine hearts (n = 27) to further understanding of their influence on the cellular mechanisms underlying generation of cardiac arrhythmias. Purkinje fibers from normal or infarcted hearts were superfused with modified Krebs' solution (37 degrees C) with or without epinephrine (2 or 15 microM) and equilibrated with a 97% O2-3% CO2 gas mixture (control). Transmembrane action potentials were recorded using conventional microelectrode techniques, and Purkinje fibers were exposed to anesthetic concentrations equivalent to 2.0 MAC. Normal Purkinje fibers were not spontaneously active unless exposed to epinephrine. All anesthetics (enflurane greater than halothane, isoflurane; P less than 0.05) increased automaticity of normal Purkinje fibers exposed to either epinephrine concentration. Partially depolarized Purkinje fibers from infarcted hearts were either spontaneously active or were quiescent. For ischemic fibers that beat spontaneously, abnormal automaticity was sustained (duration greater than 300 s) or periodic (duration less than 300 s). Sustained abnormal automaticity was elicited by epinephrine (15 microM) in some quiescent partially depolarized fibers. None of the anesthetics affected the rate of sustained abnormal automaticity, regardless of whether the induction of such automaticity required epinephrine, nor did anesthetics significantly affect the duration of trains of periodic abnormal automaticity. Finally, quiescent, partially depolarized Purkinje fibers were tested for triggered rhythmic activity during pacing at a cycle length of 800 ms.(ABSTRACT TRUNCATED AT 250 WORDS)

Author List

Laszlo A, Polic S, Kampine JP, Turner LA, Atlee JL 3rd, Bosnjak ZJ

MESH terms used to index this publication - Major topics in bold

Action Potentials
Animals
Cardiac Pacing, Artificial
Dogs
Electrophysiology
Enflurane
Halothane
Heart
Isoflurane
Microelectrodes
Myocardial Infarction
Purkinje Fibers