Linear O2 Use-Pressure-Volume Area Relation from Curved End-Systolic Pressure-Volume Relation of the Blood-Perfused Rat Left Ventricle.

1998 ◽  
Vol 48 (3) ◽  
pp. 197-204 ◽  
Author(s):  
Yoshiki HATA ◽  
Taisuke SAKAMOTO ◽  
Shingo HOSOGI ◽  
Tohru OHE ◽  
Hiroyuki SUGA ◽  
...  
Keyword(s):  
Left Ventricle ◽  
Systolic Pressure ◽  
Volume Relation

Similar normalized Emax and O2 consumption-pressure-volume area relation in rabbit and dog

1988 ◽  
Vol 255 (2) ◽  
pp. H366-H374 ◽  
Author(s):  
Y. Goto ◽  
B. K. Slinker ◽  
M. M. LeWinter
Keyword(s):  
Left Ventricle ◽  
Systolic Pressure ◽  
Energy Conversion Efficiency ◽  
Left Ventricular ◽  
Energy Transduction ◽  
Base Line ◽  
Contractile State ◽  
Primary Determinant ◽  
Heart Size ◽  
Volume Relation

The end-systolic pressure-volume relation (ESPVR), a measure of ventricular contractile state, and systolic pressure-volume area (PVA), a primary determinant of cardiac oxygen consumption per beat (VO2), have been derived from the pressure-volume diagram of the cross-circulated dog left ventricle. The slope of the PVA-VO2 relation represents the efficiency of chemomechanical energy transduction of the contractile machinery. To see whether these relationships were similar in other animals, we studied the isovolumic ESPVR and the VO2-PVA relation in nine excised, cross-circulated rabbit left ventricles. The base-line ESPVR was linear (r = 0.94-0.99) with the slope (Emax) and volume-axis intercept (V0) equal to 83.4 +/- 18.3 mmHg/ml and 0.43 +/- 0.17 ml, respectively. When normalized for left ventricular weight, Emax (4.1 +/- 1.1 mmHg.ml-1.100 g) and V0 (8.9 +/- 3.7 ml/100 g) were similar to values reported for the dog left ventricle. The correlation between PVA and VO2 was linear (r = 0.93-1.00), and the slope (1.90 X 10(-5) +/- 0.44 X 10(-5) ml O2.mmHg-1.ml-1) and VO2-axis intercept (0.040 +/- 0.009 ml O2.beat-1.100 g-1) were similar to values found in the dog left ventricle. Hence, despite the greatly different heart size, the base-line contractile state and chemomechanical energy conversion efficiency of the excised, cross-circulated rabbit left ventricle are similar to those of the dog left ventricle.

scholarly journals Nonlinearity and load sensitivity of end-systolic pressure-volume relation of canine left ventricle in vivo.

Circulation ◽  
1991 ◽  
Vol 83 (1) ◽  
pp. 315-327 ◽  
Author(s):  
E T van der Velde ◽  
D Burkhoff ◽  
P Steendijk ◽  
J Karsdon ◽  
K Sagawa ◽  
...  
Keyword(s):  
Left Ventricle ◽  
Systolic Pressure ◽  
Volume Relation

scholarly journals Single-beat estimation of the slope of the end-systolic pressure-volume relation in the human left ventricle.

Circulation ◽  
1991 ◽  
Vol 83 (1) ◽  
pp. 202-212 ◽  
Author(s):  
M Takeuchi ◽  
Y Igarashi ◽  
S Tomimoto ◽  
M Odake ◽  
T Hayashi ◽  
...  
Keyword(s):  
Left Ventricle ◽  
Systolic Pressure ◽  
Volume Relation ◽  
Human Left Ventricle

Transient vs. steady end-systolic pressure-volume relation in dog left ventricle

1987 ◽  
Vol 252 (5) ◽  
pp. H998-H1004 ◽  
Author(s):  
Y. Igarashi ◽  
Y. Goto ◽  
O. Yamada ◽  
T. Ishii ◽  
H. Suga
Keyword(s):  
Regression Analysis ◽  
Steady State ◽  
Linear Regression ◽  
Left Ventricle ◽  
Ejection Fraction ◽  
Linear Regression Analysis ◽  
Systolic Pressure ◽  
Contractile State ◽  
End Diastolic Volume ◽  
Volume Relation

We compared transient slope of end-systolic pressure-volume line (T-Emax) with steady Emax (S-Emax) in isolated cross-circulated canine left ventricles. T-Emax is the slope of the end-systolic pressure-volume line (ESPVL) determined from the last steady-state ejecting contraction (SEC) and the first transient isovolumic contraction produced by end-diastolic volume clamp. S-Emax is the slope of ESPVL determined from five steady-state contractions by linear regression analysis. We obtained three T-Emax values in the same contractile state by changing ejection fraction (EF) of SEC to three levels (range 14-58%) from the same end-diastolic volume. T-Emax variably increased with EF in any contractile state. The ratios of the three T-Emax values to the same S-Emax value was 1.08 +/- 0.04 (11 ventricles, means +/- SE) for high EF, 0.87 +/- 0.06 for middle EF, and 0.69 +/- 0.07 for low EF in control contractile state. These ratios decreased under epinephrine and increased under propranolol. We conclude that T-Emax depends not only on EF but also on contractile state in isolated dog left ventricles.

Determinants of end-systolic pressure during different load alterations in the in situ left ventricle

1994 ◽  
Vol 267 (5) ◽  
pp. H1895-H1906 ◽  
Author(s):  
L. P. van der Linden ◽  
E. T. van der Velde ◽  
H. C. van Houwelingen ◽  
A. V. Bruschke ◽  
J. Baan
Keyword(s):  
Left Ventricle ◽  
Systolic Pressure ◽  
Single Equation ◽  
Random Coefficients ◽  
Systolic Volume ◽  
Inotropic State ◽  
End Systolic Volume ◽  
Anesthetized Dogs ◽  
Volume Relation

Because of the strong dependency of the end-systolic pressure-volume relation on the type of transient loading intervention in the in situ left ventricle (LV), experiments in the basal inotropic state in 16 open-chest anesthetized dogs were reanalyzed to find additional variables to model and predict end-systolic pressure (ESP) of both afterloading and preloading interventions by a single equation. Random-coefficients regression analysis was performed on 22 experiments in the basal inotropic state simultaneously, yielding an overall R2 of 0.97. The major part of total variance of ESP was due to linear terms of end-systolic volume (ESV) (74%) and stroke volume (SV) (19%). The SV effect was consistently negative and quantitatively quite important. An average load-independent end-systolic elastance of 6.7 mmHg/ml and an average SV effect of -5.7 mmHg/ml ejected were estimated, separating the “force-length” property from shortening effects in the in situ LV. History-related effects appeared to be only minor.

scholarly journals Linearity of the left ventricular end-systolic pressure-volume relation in patients with severe heart failure

1989 ◽  
Vol 14 (1) ◽  
pp. 127-134 ◽  
Author(s):  
Constantine N. Aroney ◽  
Howard C. Herrmann ◽  
Marc J. Semigran ◽  
G. William ◽  
Charles A. Boucher ◽  
...  
Keyword(s):  
Heart Failure ◽  
Severe Heart Failure ◽  
Systolic Pressure ◽  
Left Ventricular ◽  
Volume Relation

Rhythm effects on contractility of the beating isovolumic left ventricle

1960 ◽  
Vol 199 (6) ◽  
pp. 1115-1120 ◽  
Author(s):  
B. Lendrum ◽  
H. Feinberg ◽  
E. Boyd ◽  
L. N. Katz
Keyword(s):  
Heart Rate ◽  
Left Ventricle ◽  
Systolic Pressure ◽  
Ventricular Volume ◽  
Contractile Force ◽  
Postextrasystolic Potentiation ◽  
Pressure Development ◽  
Induced Changes ◽  
Electrical Alternans

Variation in contractile force of the isovolumic contracting left ventricle of the dog was studied in open-chested in situ hearts. The electrocardiogram and intraventricular pressures were recorded at various heart volumes. Spontaneous changes in heart rate and rhythm occurred at all volumes. Isovolumic systolic pressure development (contractile force) varied with rate and rhythm. Contractile force increased with heart rate (treppe) regardless of pacemaker origin. When a premature beat was followed by a compensatory pause, the premature beat showed a decrease and the next beat an increase in contractile force (postextrasystolic potentiation). The magnitude of the changes varied directly with the prematurity of the beat. Mechanical alternans was observed with electrical alternans, despite the absence of significant volume change. Rate-induced changes, postextrasystolic potentiation and mechanical alternans were additive when they occurred simultaneously. For practical purposes, ventricular volume (filling), hence muscle fiber length, remained constant during these rate and rhythm change, therefore could not affect the strength of contraction. Contractile force changes directly attributable to rate and rhythm changes do, therefore, occur in the intact mammalian heart.

Ventricular systolic interdependence: volume elastance model in isolated canine hearts

1987 ◽  
Vol 253 (6) ◽  
pp. H1381-H1390 ◽  
Author(s):  
W. L. Maughan ◽  
K. Sunagawa ◽  
K. Sagawa
Keyword(s):  
Left Ventricle ◽  
Right Ventricle ◽  
Cross Talk ◽  
Systolic Pressure ◽  
Left Ventricular ◽  
Ventricular Free Wall ◽  
Free Wall ◽  
Right Ventricular Free Wall ◽  
Systolic Volume ◽  
The Right

To analyze the interaction between the right and left ventricle, we developed a model that consists of three functional elastic compartments (left ventricular free wall, septal, and right ventricular free wall compartments). Using 10 isolated blood-perfused canine hearts, we determined the end-systolic volume elastance of each of these three compartments. The functional septum was by far stiffer for either direction [47.2 +/- 7.2 (SE) mmHg/ml when pushed from left ventricle and 44.6 +/- 6.8 when pushed from right ventricle] than ventricular free walls [6.8 +/- 0.9 mmHg/ml for left ventricle and 2.9 +/- 0.2 for right ventricle]. The model prediction that right-to-left ventricular interaction (GRL) would be about twice as large as left-to-right interaction (GLR) was tested by direct measurement of changes in isovolumic peak pressure in one ventricle while the systolic pressure of the contralateral ventricle was varied. GRL thus measured was about twice GLR (0.146 +/- 0.003 vs. 0.08 +/- 0.001). In a separate protocol the end-systolic pressure-volume relationship (ESPVR) of each ventricle was measured while the contralateral ventricle was alternatively empty and while systolic pressure was maintained at a fixed value. The cross-talk gain was derived by dividing the amount of upward shift of the ESPVR by the systolic pressure difference in the other ventricle. Again GRL measured about twice GLR (0.126 +/- 0.002 vs. 0.065 +/- 0.008). There was no statistical difference between the gains determined by each of the three methods (predicted from the compartment elastances, measured directly, or calculated from shifts in the ESPVR). We conclude that systolic cross-talk gain was twice as large from right to left as from left to right and that the three-compartment volume elastance model is a powerful concept in interpreting ventricular cross talk.

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