PMID- 2912198
OWN - NLM
STAT- MEDLINE
DCOM- 19890223
LR  - 20171213
IS  - 0002-9513 (Print)
IS  - 0002-9513 (Linking)
VI  - 256
IP  - 1 Pt 2
DP  - 1989 Jan
TI  - Single-beat evaluation of left ventricular inotropic state in conscious dogs.
PG  - H56-65
AB  - Two competing left ventricular elastic-resistive (ER) models were used to predict 
      parameter values from pressure, volume, and time data of a single ejective beat 
      in conscious dogs during control, enhanced (dobutamine), and decreased 
      (propranolol) inotropic states. The animals were instrumented with three pairs of 
      microcrystals and a transducer to measure intraventricular volume and pressure. 
      Results showed that with the ER nonlinear model (ERNL), parameter values in all 
      animals lay within the physiological range. These were the slope (Emax) and the 
      intercept (V0) of the isovolumic end-systolic pressure-volume relationship 
      (ESPVR), the slope of the end-diastolic pressure-volume relationship (Ed), the 
      time to Emax (Tmax), the normalized time to end of activation (A), and the 
      resistive constant (K). In the two models, the normalized SE of the estimate of 
      data fitting was below 0.2 Emax, as estimated from a single beat, responded to 
      changes in contractility in a significantly more consistent fashion than the 
      slope of ESPVRs (Ees) generated by preload maneuvers in conscious dogs. 
      Single-beat estimated Tmax and K with the ERNL model did also respond 
      consistently to contractility changes, whereas with the elastic resistive linear 
      (ERL) model, K did not reproduce the experimental findings with decreased 
      inotropic state. We conclude that 1) the ERNL model can be employed to assess 
      contractility changes in conscious dogs from data of a single ejective beat, and 
      2) these changes are better indicated by single-beat estimated Emax than by Ees 
      calculated from conventional ESPVRs.
FAU - Lascano, E C
AU  - Lascano EC
AD  - Departamento de Investigacion y Docencia de la Fundacion Favaloro, Universidad de 
      Buenos Aires, Argentina.
FAU - Negroni, J A
AU  - Negroni JA
FAU - Barra, J G
AU  - Barra JG
FAU - Crottogini, A J
AU  - Crottogini AJ
FAU - Pichel, R H
AU  - Pichel RH
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Am J Physiol
JT  - The American journal of physiology
JID - 0370511
SB  - IM
MH  - Algorithms
MH  - Animals
MH  - Dogs
MH  - Heart/*physiology
MH  - Hemodynamics
MH  - *Myocardial Contraction
MH  - Reference Values
MH  - Ventricular Function
EDAT- 1989/01/01 00:00
MHDA- 1989/01/01 00:01
CRDT- 1989/01/01 00:00
PHST- 1989/01/01 00:00 [pubmed]
PHST- 1989/01/01 00:01 [medline]
PHST- 1989/01/01 00:00 [entrez]
AID - 10.1152/ajpheart.1989.256.1.H56 [doi]
PST - ppublish
SO  - Am J Physiol. 1989 Jan;256(1 Pt 2):H56-65. doi: 10.1152/ajpheart.1989.256.1.H56.