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Catecholamine metabolism in heart failure patients and healthy control subjects
M Lehmann1, G Hasenfuss, L Samek
1Medical University Clinic, Department of Sports and Performance Medicine, Freiburg/Brsg., Fed. Rep. of Germany.
Insights
Catecholamine metabolism is altered in heart disease, with elevated excretion and reduced clearance in early stages. Severe heart failure shows reduced dopamine elimination and lower exercise-induced noradrenaline levels.
Area of Science:
- Cardiology
- Endocrinology
- Pharmacology
Background:
- Catecholamine metabolism plays a crucial role in cardiovascular function.
- Understanding these metabolic pathways is vital for managing heart conditions.
Purpose of the Study:
- To investigate catecholamine metabolism in patients with coronary heart disease and dilated cardiomyopathy.
- To assess the impact of left-heart damage severity on catecholamine levels and clearance.
Main Methods:
- Examined plasma and urinary catecholamine patterns in patients and healthy controls.
- Determined catecholamine plasma half-life and metabolism after levodopa administration.
- Assessed ejection fraction to categorize heart damage severity.
Main Results:
- Early heart disease showed elevated catecholamine excretion and reduced plasma clearance.
- Severe heart failure exhibited reduced 24-hour dopamine elimination (34-41% of normal).
- Exercise-induced plasma noradrenaline was significantly lower in severe heart failure patients.
Conclusions:
- Altered catecholamine metabolism is a hallmark of heart disease progression.
- Reduced dopamine elimination and altered noradrenaline response are observed in severe heart failure.
- Levodopa administration significantly increased dopamine levels in heart failure patients.
Abstract:
Parameter of catecholamine metabolism were examined in patients (Groups II to V) in chronic, stable stages of coronary heart disease (n = 45), dilated cardiomyopathy (n = 17) and healthy control subjects (Group I). Plasma and urinary catecholamine patterns, catecholamine plasma half-life and catecholamine metabolism following administration of levodopa were determined. In cases of slight (Group II, ejection fraction (EF) 54 +/- 7%) to marked left-heart damage (Group III, EF 44 +/- 5%), the findings indicate elevated catecholamine excretion and a beginning reduction of plasma clearance as the cause of excessive, circulating and renally excreted catecholamines (applies to noradrenaline, less to adrenaline). The renal 24-h dopamine elimination is already slightly reduced in these patients. In cases of severe left-heart damage, the findings are not uniform. In some cases, noradrenaline at rest and at comparable exercise levels are elevated (Group IV, EF 20 +/- 11%), in some cases they are normal (Group V, EF 16 +/- 4%). The 24-h dopamine elimination is reduced in both groups to 34-41% of normal. Noradrenaline and adrenaline elimination is normal, or reduced (Group V, adrenaline). The exercise-induced, maximum plasma noradrenaline concentrations in Group IV and V are much lower (33-40% of normal) than in the healthy control individuals and patients in Groups II and III. Oral administration of 2-4 g levodopa per day result in a 20- to 40-fold dopamine increase in patients with heart failure (Group IV) and healthy control persons (Group I) (free and conjugated plasma dopamine, as well as free urinary dopamine).(ABSTRACT TRUNCATED AT 250 WORDS)