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Estimating left ventricular offset volume using dual-frequency conductance catheters.

T J Gawne·K S Gray·R E Goldstein
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Abstract

The measurement of left ventricular volume by the conductance-catheter technique has many advantages, but it is difficult to determine absolute volumes with this method. Current procedure requires that a bolus of concentrated hypertonic saline be injected to measure absolute volume. It also demands that the subject be in a steady state and that measurements only be made at discrete intervals. The saline bolus may affect the cardiovascular state of the subject. This paper describes a new technique for estimating absolute volume utilizing the conductance catheter that relies on the different frequency responses of blood and muscle. Good correlation between the salt-injection method and the dual-frequency method was found in nine closed-chest pigs anesthetized with pentobarbital sodium (r = 0.922). Further refinements may extend the utility of the dual-frequency approach.

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AnimalsBlood VolumeCatheterizationElectric ConductivityElectrophysiologyHeartHeart VentriclesStroke VolumeSwineSystoleJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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T J Gawne, K S Gray, R E Goldstein. 1987. Estimating left ventricular offset volume using dual-frequency conductance catheters.. https://doi.org/10.1152/jappl.1987.63.2.872

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