ABSENCE OF DIRECT EFFECT OF EJECTION VELOCITY ON LV RELAXATION RATE IN LV VOLUME CONTROLLED ISOLATED CANINE HEARTS.

Masafumi Kitakaze; M. Hori; Y. Ishida; M. Fukunami; H. Kusuoka; T. Kigiya; A. Kitabatake; M. Inoue; H. Abe; K. Tsujioka; S. Nakajima

ABSENCE OF DIRECT EFFECT OF EJECTION VELOCITY ON LV RELAXATION RATE IN LV VOLUME CONTROLLED ISOLATED CANINE HEARTS.

Masafumi Kitakaze, M. Hori, Y. Ishida, M. Fukunami, H. Kusuoka, T. Kigiya, A. Kitabatake, M. Inoue, H. Abe, K. Tsujioka, S. Nakajima

School of Medicine

Research output: Contribution to journal › Conference article › peer-review

Abstract

Augmented stroke volume (SV) accompanies an increase in ejection velocity (Ve). To determine whether Ve directly affects the LV relaxation rate irrespective of SV changes, the time constant (T) of isovolumic LV pressure (LVP) decay was studied in 8 isolated canine hearts. A water-filled balloon was inserted into LV cavity and instantaneous LV volume was controlled by servo-pump. To eliminate the effect of SV, end-systolic and end-diastolic volumes were clamped and LV was allowed to eject with 3-5 different velocities under two conditions; with mid-ejection time and with end of ejection unchanged. In any condition, T was not significantly altered by Ve changes. Thus, we conclude that LV relaxation rate is not influenced by ejection velocity. Enhanced LV relaxation rate in augmented SV may be due to the direct effect of the extent of muscle shortening.

Original language	English (US)
Pages (from-to)	126-127
Number of pages	2
Journal	Japanese journal of medical electronics and biological engineering
Volume	22
State	Published - Apr 1 1984

ASJC Scopus subject areas

Biomedical Engineering

Cite this

@article{c097682328d34c8c81babd90bff70137,

title = "ABSENCE OF DIRECT EFFECT OF EJECTION VELOCITY ON LV RELAXATION RATE IN LV VOLUME CONTROLLED ISOLATED CANINE HEARTS.",

abstract = "Augmented stroke volume (SV) accompanies an increase in ejection velocity (Ve). To determine whether Ve directly affects the LV relaxation rate irrespective of SV changes, the time constant (T) of isovolumic LV pressure (LVP) decay was studied in 8 isolated canine hearts. A water-filled balloon was inserted into LV cavity and instantaneous LV volume was controlled by servo-pump. To eliminate the effect of SV, end-systolic and end-diastolic volumes were clamped and LV was allowed to eject with 3-5 different velocities under two conditions; with mid-ejection time and with end of ejection unchanged. In any condition, T was not significantly altered by Ve changes. Thus, we conclude that LV relaxation rate is not influenced by ejection velocity. Enhanced LV relaxation rate in augmented SV may be due to the direct effect of the extent of muscle shortening.",

author = "Masafumi Kitakaze and M. Hori and Y. Ishida and M. Fukunami and H. Kusuoka and T. Kigiya and A. Kitabatake and M. Inoue and H. Abe and K. Tsujioka and S. Nakajima",

year = "1984",

month = apr,

day = "1",

language = "English (US)",

volume = "22",

pages = "126--127",

journal = "Japanese journal of medical electronics and biological engineering",

issn = "0021-3292",

publisher = "Nihon M E Gakkai",

}

TY - JOUR

T1 - ABSENCE OF DIRECT EFFECT OF EJECTION VELOCITY ON LV RELAXATION RATE IN LV VOLUME CONTROLLED ISOLATED CANINE HEARTS.

AU - Kitakaze, Masafumi

AU - Hori, M.

AU - Ishida, Y.

AU - Fukunami, M.

AU - Kusuoka, H.

AU - Kigiya, T.

AU - Kitabatake, A.

AU - Inoue, M.

AU - Abe, H.

AU - Tsujioka, K.

AU - Nakajima, S.

PY - 1984/4/1

Y1 - 1984/4/1

N2 - Augmented stroke volume (SV) accompanies an increase in ejection velocity (Ve). To determine whether Ve directly affects the LV relaxation rate irrespective of SV changes, the time constant (T) of isovolumic LV pressure (LVP) decay was studied in 8 isolated canine hearts. A water-filled balloon was inserted into LV cavity and instantaneous LV volume was controlled by servo-pump. To eliminate the effect of SV, end-systolic and end-diastolic volumes were clamped and LV was allowed to eject with 3-5 different velocities under two conditions; with mid-ejection time and with end of ejection unchanged. In any condition, T was not significantly altered by Ve changes. Thus, we conclude that LV relaxation rate is not influenced by ejection velocity. Enhanced LV relaxation rate in augmented SV may be due to the direct effect of the extent of muscle shortening.

AB - Augmented stroke volume (SV) accompanies an increase in ejection velocity (Ve). To determine whether Ve directly affects the LV relaxation rate irrespective of SV changes, the time constant (T) of isovolumic LV pressure (LVP) decay was studied in 8 isolated canine hearts. A water-filled balloon was inserted into LV cavity and instantaneous LV volume was controlled by servo-pump. To eliminate the effect of SV, end-systolic and end-diastolic volumes were clamped and LV was allowed to eject with 3-5 different velocities under two conditions; with mid-ejection time and with end of ejection unchanged. In any condition, T was not significantly altered by Ve changes. Thus, we conclude that LV relaxation rate is not influenced by ejection velocity. Enhanced LV relaxation rate in augmented SV may be due to the direct effect of the extent of muscle shortening.

UR - http://www.scopus.com/inward/record.url?scp=0021410326&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0021410326&partnerID=8YFLogxK

M3 - Conference article

AN - SCOPUS:0021410326

SN - 0021-3292

VL - 22

SP - 126

EP - 127

JO - Japanese journal of medical electronics and biological engineering

JF - Japanese journal of medical electronics and biological engineering

ER -

ABSENCE OF DIRECT EFFECT OF EJECTION VELOCITY ON LV RELAXATION RATE IN LV VOLUME CONTROLLED ISOLATED CANINE HEARTS.

Abstract

ASJC Scopus subject areas

Other files and links

Fingerprint

Cite this