start-ver=1.4
cd-journal=joma
no-vol=66
cd-vols=
no-issue=6
article-no=
start-page=435
end-page=442
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2012
dt-pub=201212
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Effects of Propofol on Left Ventricular Mechanoenergetics in the Excised Cross-circulated Canine Heart
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=Although propofol is commonly used for general anesthesia, its direct effects on left ventricular (LV) contractility and energetics remain unknown. Accordingly, we studied the effects of intracoronary propofol on excised cross-circulated canine hearts using the framework of the Emax (a contractility index)-PVA (systolic pressure-volume area, a measure of total mechanical energy)-Vo2 (myocardial oxygen consumption per beat) relationship. We obtained 1) the Vo2-PVA relationship of isovolumic contractions with varied LV volumes at a constant Emax, 2) the Vo2-PVA relationship with varied LV volumes at a constant intracoronary concentration of propofol, and 3) the Vo2-PVA relationship under increased intracoronary concentrations of either propofol or CaCl2 at a constant LV volume to assess the cardiac mechanoenergetic effects of propofol. We found that propofol decreased Emax dose-dependently. The slope of the linear Vo2-PVA relationship (oxygen cost of PVA) remained unchanged by propofol. The PVA-independent Vo2-Emax relationship (oxygen cost of Emax) was the same for propofol and Ca2＋. In conclusion, propofol showed a direct negative inotropic effect on LV. At its clinical concentrations, decreases in contractility by propofol were relatively small. Propofol shows mechanoenergetic effects on the LV that are similar to those of Ca2＋ blockers or ß-antagonists—i.e., it exerts negative inotropic effects without changing the oxygen costs of Emax and PVA.
en-copyright=
kn-copyright=

en-aut-name=FujinakaWaso
en-aut-sei=Fujinaka
en-aut-mei=Waso
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=ShimizuJuichiro
en-aut-sei=Shimizu
en-aut-mei=Juichiro
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=IribeGentaro
en-aut-sei=Iribe
en-aut-mei=Gentaro
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=ImaokaTakeshi
en-aut-sei=Imaoka
en-aut-mei=Takeshi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

en-aut-name=OshimaYu
en-aut-sei=Oshima
en-aut-mei=Yu
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=5
ORCID=

en-aut-name=KiyookaTakahiko
en-aut-sei=Kiyooka
en-aut-mei=Takahiko
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=6
ORCID=

en-aut-name=MoritaKiyoshi
en-aut-sei=Morita
en-aut-mei=Kiyoshi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=7
ORCID=

en-aut-name=MohriaSatoshi
en-aut-sei=Mohria
en-aut-mei=Satoshi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=8
ORCID=

affil-num=1
en-affil=
kn-affil=Department of Cardiovascular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences

affil-num=2
en-affil=
kn-affil=Department of Cardiovascular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences

affil-num=3
en-affil=
kn-affil=Department of Cardiovascular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences

affil-num=4
en-affil=
kn-affil=Department of Cardiovascular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences

affil-num=5
en-affil=
kn-affil=Department of Cardiovascular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences

affil-num=6
en-affil=
kn-affil=Department of Cardiovascular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences

affil-num=7
en-affil=
kn-affil=Department of Anesthesiology and Resuscitology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences

affil-num=8
en-affil=
kn-affil=Department of Cardiovascular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
en-keyword=anesthesia
kn-keyword=anesthesia
en-keyword=heart
kn-keyword=heart
en-keyword=contractility
kn-keyword=contractility
en-keyword=myocardial oxygen consumption
kn-keyword=myocardial oxygen consumption
END