Development of a multifrequency conductance catheter-based system to determine LV function in mice

Marc D Feldman, Yi Mao, Jonathan W. Valvano, John A. Pearce, Gregory L. Freeman

Research output: Contribution to journalArticle

46 Citations (Scopus)

Abstract

Transgenic mice offer a valuable way to relate gene products to phenotype, but the ability to assess the cardiovascular phenotype with pressure-volume analysis has lagged. Conductance measurement offers a method to generate an instantaneous left ventricular (LV) volume signal in the mouse but has been limited by the volume signal being a combination of blood and LV muscle. We hypothesized that by developing a mouse conductance system that operates at several simultaneous frequencies, we could identify and correct for the myocardial contribution to the instantaneous volume signal. This hypothesis is based on the assumption that mouse myocardial conductivity will vary with frequency, whereas mouse blood conductivity will not. Consistent with this hypothesis, we demonstrated that at higher excitation frequency, greater end-diastolic and endsystolic conductance are detected, as well as a smaller difference between the two. We then empirically solved for LV blood volume using two frequencies. We combined measured resistivity of mouse myocardium with an analytic approach and extracted an estimate of LV blood volume from the raw conductance signal. Development of a multifrequency catheter-based system to determine LV function could be a tool to assess cardiovascular phenotype in transgenic mice.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Heart and Circulatory Physiology
Volume279
Issue number3 48-3
StatePublished - 2000

Fingerprint

Left Ventricular Function
Catheters
Blood Volume
Phenotype
Transgenic Mice
Myocardium
Pressure
Muscles
Genes

Keywords

  • Left ventricular function
  • Myocardial resistivity
  • Pressure-volume analysis
  • Transgenic mouse

ASJC Scopus subject areas

  • Physiology
  • Physiology (medical)

Cite this

Development of a multifrequency conductance catheter-based system to determine LV function in mice. / Feldman, Marc D; Mao, Yi; Valvano, Jonathan W.; Pearce, John A.; Freeman, Gregory L.

In: American Journal of Physiology - Heart and Circulatory Physiology, Vol. 279, No. 3 48-3, 2000.

Research output: Contribution to journalArticle

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