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Adverse effects of epinephrine in patients with advanced left ventricular dysfunction: analysis of
K Yamamoto1, K Kodama, T Masuyama
1Cardiovascular Division, Osaka Police Hospital, Japan.
Insights
Epinephrine improves ventriculo-arterial coupling and work efficiency in healthy individuals and those with mild left ventricular dysfunction. However, in advanced dysfunction, epinephrine fails to improve these metrics.
Area of Science:
- Cardiology
- Physiology
Background:
- Ventriculo-arterial coupling is crucial for cardiac efficiency.
- Epinephrine's effects on this coupling in varying degrees of left ventricular dysfunction are not fully understood.
Purpose of the Study:
- To investigate how epinephrine affects ventriculo-arterial coupling and ventricular work efficiency in patients with normal and impaired left ventricular function.
Main Methods:
- A conductance catheter was used in 19 patients categorized into three groups based on left ventricular function.
- Patients received two doses of epinephrine (0.05 and 0.1 µg/kg/min).
- Changes in end-systolic elastance, effective arterial elastance, their ratio, and ventricular work efficiency were analyzed.
Main Results:
- Epinephrine decreased the ratio of effective arterial elastance to end-systolic elastance and increased ventricular work efficiency in normal and mildly dysfunctional groups.
- In patients with advanced left ventricular dysfunction (ejection fraction 28-40%), epinephrine did not decrease this ratio and decreased ventricular work efficiency.
Conclusions:
- Epinephrine can modulate ventriculo-arterial coupling to enhance ventricular work efficiency in normal and mildly impaired left ventricular function.
- In advanced left ventricular dysfunction, high-dose epinephrine does not improve ventriculo-arterial coupling or ventricular work efficiency.
Abstract:
We examined the response of ventriculo-arterial coupling to epinephrine in 19 patients with normal left ventricular function and with left ventricular dysfunction of various degrees using a conductance catheter. They were divided into three groups: group I, seven patients without left ventricular wall motion abnormality; group II, six patients with ejection fraction of 45-60%; group III, six patients with ejection fraction of 28-40%. Changes in the slope of the end-systolic pressure-volume relationship (end-systolic elastance), the effective arterial elastance, the ratio of effective arterial elastance to end-systolic elastance and the ventricular work efficiency during administration of two different doses of epinephrine (0.05 and 0.1 micrograms/kg/min) were compared among the three groups. At baseline there were no significant differences among the three groups in the ratio of effective arterial elastance to end-systolic elastance, or ventricular work efficiency. At the lower dose of epinephrine, the mean ratio of effective arterial elastance to end-systolic elastance decreased and the mean ventricular work efficiency increased in any groups. At the higher dose of epinephrine the mean ratio of effective arterial elastance to end-systolic elastance further decreased and the mean ventricular work efficiency further increased in groups I and II. However, the mean ratio of effective arterial elastance to end-systolic elastance did not decrease but the mean ventricular work efficiency even decreased in group III. Thus, in patients with advanced left ventricular dysfunction, even a high dose of epinephrine does not modulate the ventriculo-arterial coupling to increase ventricular work efficiency.