Comparative effects of isoproterenol and dopamine on myocardial oxygen consumption, blood flow distribution and total body oxygen consumption in conscious lambs with and without an aortopulmonary left to right shunt

Beatrijs Bartelds, Jan Willem C. Gratama, Koos J. Meuzelaar, Michiel Dalinghaus, Jan H. Koers, Willem F. Heikens, Willem G. Zijlstra, Jaap R.G. Kuipers*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

10 Citations (Scopus)

Abstract

Objectives.
We sought to study the effects of catecholamines on myocardial oxygen consumption (Vo2), regional blood flows and total body Vo2 in lambs with circulatory congestion.

Background.
Catecholamines are often used to support cardiovascular function in children with circulatory congestion because they increase contractility as well as heart rate. However, these changes increase myocardial oxygen demand and thus can lead to a mismatch between myocardial oxygen supply and demand. Catecholamines can also change regional blood flows and Vo2 unfavorably.

Methods.
We infused isoproterenol (0.1 μg/kg body weight per rain) and dopamine (10 μg/kg per min) and measured myocardial and total body Vo2 and regional blood flows in chronically instrumented 7-week old lambs with and without a left to right shunt.

Results.
Isoproterenol increased myocardial Vo2, parallel to the increase in heart rate. However, myocardial blood flow and, consequently, oxygen supply also increased. This increase out-weighed the increase in myocardial Vo2, so that myocardial oxygen extraction decreased. Isoproterenol did not change blood flow distribution. Isoproterenol increased total body-Vo2; however, systemic oxygen supply increased even more, so that oxygen extraction decreased and mixed venous oxygen saturation increased. In contrast, dopamine had no or little effect on myocardial Vo2 or blood flow distribution.

Conclusions.
We conclude that the catecholamines isoproterenol and dopamine do not lead to a mismatch between myocardial oxygen supply and demand, nor do they change blood flow distribution unfavorably in 7-week old lambs with a left to right shunt. We demonstrated that isoproterenol is superior to dopamine, because it shifts the balance between oxygen supply and consumption toward supply so that systemic oxygen extraction reserve increases.

Original languageEnglish
Pages (from-to)473-481
Number of pages9
JournalJournal of the American College of Cardiology
Volume31
Issue number2
DOIs
Publication statusPublished - Feb 1998
Externally publishedYes

Bibliographical note

©1998 by the American College of Cardiology

Fingerprint

Dive into the research topics of 'Comparative effects of isoproterenol and dopamine on myocardial oxygen consumption, blood flow distribution and total body oxygen consumption in conscious lambs with and without an aortopulmonary left to right shunt'. Together they form a unique fingerprint.

Cite this