Evidence and quantitation of left ventricular systolic resistance

S. G. Shroff, J. S. Janicki, K. T. Weber

Research output: Contribution to journalArticle

Abstract

Instantaneous left ventricular pressure is a function of both volume (elastic behavior) and flow (resistive behavior). However, a quantitative description of ventricular resistance and its effects on ventricular performance remains to be elucidated. Accordingly, ventricular resistive behavior was studied in six isolated canine hearts. Our experimental findings indicate 1) for a specified time (t(s)), volume (V(s)), and contractile state (CS), the ventricular pressure-flow relation was linear (r = 0.96-0.99) within the range of flows examined (0-250 ml/s); 2) ventricular resistance increased with increments in t(s), V(s), and CS, whereas the zero-pressure flow intercept was invariant; 3) resistance could be uniquely quantified as a linear function of isovolumetric pressure. In six experiments, the slope of this relationship ranged from 1.1 to 2.1 x 10-3 s/ml while the intercept did not differ from zero; and 4) end-systolic elastance, estimated from end-systolic pressure-volume data, was in substantial error under the conditions of finite (>35 ml/s) end-systolic flows. Finally, the results from a computer simulation of the coupled ventricular-arterial system indicated that ventricular resistance primarily affects the pulsatile nature of aortic flow. The unique isovolumetric pressure-resistance relation suggests that the rate-limiting properties of the contractile process may be causally related to the observed ventricular resistive behavior.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Heart and Circulatory Physiology
Volume18
Issue number2
StatePublished - 1985
Externally publishedYes

Fingerprint

Ventricular Pressure
Pressure
Computer Simulation
Canidae
Blood Pressure

All Science Journal Classification (ASJC) codes

  • Physiology

Cite this

Evidence and quantitation of left ventricular systolic resistance. / Shroff, S. G.; Janicki, J. S.; Weber, K. T.

In: American Journal of Physiology - Heart and Circulatory Physiology, Vol. 18, No. 2, 1985.

Research output: Contribution to journalArticle

@article{26e62170db9740f3ae88d400903bb666,
title = "Evidence and quantitation of left ventricular systolic resistance",
abstract = "Instantaneous left ventricular pressure is a function of both volume (elastic behavior) and flow (resistive behavior). However, a quantitative description of ventricular resistance and its effects on ventricular performance remains to be elucidated. Accordingly, ventricular resistive behavior was studied in six isolated canine hearts. Our experimental findings indicate 1) for a specified time (t(s)), volume (V(s)), and contractile state (CS), the ventricular pressure-flow relation was linear (r = 0.96-0.99) within the range of flows examined (0-250 ml/s); 2) ventricular resistance increased with increments in t(s), V(s), and CS, whereas the zero-pressure flow intercept was invariant; 3) resistance could be uniquely quantified as a linear function of isovolumetric pressure. In six experiments, the slope of this relationship ranged from 1.1 to 2.1 x 10-3 s/ml while the intercept did not differ from zero; and 4) end-systolic elastance, estimated from end-systolic pressure-volume data, was in substantial error under the conditions of finite (>35 ml/s) end-systolic flows. Finally, the results from a computer simulation of the coupled ventricular-arterial system indicated that ventricular resistance primarily affects the pulsatile nature of aortic flow. The unique isovolumetric pressure-resistance relation suggests that the rate-limiting properties of the contractile process may be causally related to the observed ventricular resistive behavior.",
author = "Shroff, {S. G.} and Janicki, {J. S.} and Weber, {K. T.}",
year = "1985",
language = "English (US)",
volume = "18",
journal = "American Journal of Physiology",
issn = "1931-857X",
publisher = "American Physiological Society",
number = "2",

}

TY - JOUR

T1 - Evidence and quantitation of left ventricular systolic resistance

AU - Shroff, S. G.

AU - Janicki, J. S.

AU - Weber, K. T.

PY - 1985

Y1 - 1985

N2 - Instantaneous left ventricular pressure is a function of both volume (elastic behavior) and flow (resistive behavior). However, a quantitative description of ventricular resistance and its effects on ventricular performance remains to be elucidated. Accordingly, ventricular resistive behavior was studied in six isolated canine hearts. Our experimental findings indicate 1) for a specified time (t(s)), volume (V(s)), and contractile state (CS), the ventricular pressure-flow relation was linear (r = 0.96-0.99) within the range of flows examined (0-250 ml/s); 2) ventricular resistance increased with increments in t(s), V(s), and CS, whereas the zero-pressure flow intercept was invariant; 3) resistance could be uniquely quantified as a linear function of isovolumetric pressure. In six experiments, the slope of this relationship ranged from 1.1 to 2.1 x 10-3 s/ml while the intercept did not differ from zero; and 4) end-systolic elastance, estimated from end-systolic pressure-volume data, was in substantial error under the conditions of finite (>35 ml/s) end-systolic flows. Finally, the results from a computer simulation of the coupled ventricular-arterial system indicated that ventricular resistance primarily affects the pulsatile nature of aortic flow. The unique isovolumetric pressure-resistance relation suggests that the rate-limiting properties of the contractile process may be causally related to the observed ventricular resistive behavior.

AB - Instantaneous left ventricular pressure is a function of both volume (elastic behavior) and flow (resistive behavior). However, a quantitative description of ventricular resistance and its effects on ventricular performance remains to be elucidated. Accordingly, ventricular resistive behavior was studied in six isolated canine hearts. Our experimental findings indicate 1) for a specified time (t(s)), volume (V(s)), and contractile state (CS), the ventricular pressure-flow relation was linear (r = 0.96-0.99) within the range of flows examined (0-250 ml/s); 2) ventricular resistance increased with increments in t(s), V(s), and CS, whereas the zero-pressure flow intercept was invariant; 3) resistance could be uniquely quantified as a linear function of isovolumetric pressure. In six experiments, the slope of this relationship ranged from 1.1 to 2.1 x 10-3 s/ml while the intercept did not differ from zero; and 4) end-systolic elastance, estimated from end-systolic pressure-volume data, was in substantial error under the conditions of finite (>35 ml/s) end-systolic flows. Finally, the results from a computer simulation of the coupled ventricular-arterial system indicated that ventricular resistance primarily affects the pulsatile nature of aortic flow. The unique isovolumetric pressure-resistance relation suggests that the rate-limiting properties of the contractile process may be causally related to the observed ventricular resistive behavior.

UR - http://www.scopus.com/inward/record.url?scp=0022375134&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0022375134&partnerID=8YFLogxK

M3 - Article

VL - 18

JO - American Journal of Physiology

JF - American Journal of Physiology

SN - 1931-857X

IS - 2

ER -