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Published on: July 3, 2018
Serial circulating concentrations of C-reactive protein, interleukin (IL)-4, and IL-6 in patients with acute left
1Department of Internal Medicine, Hyogo Prefectural Amagasaki Hospital, Japan.
Insights
In acute heart failure, levels of C-reactive protein (CRP) and cytokines Interleukin-4 (IL-4) and Interleukin-6 (IL-6) significantly increase. These inflammatory markers decrease as heart failure symptoms resolve, highlighting dynamic changes in decompensated states.
Area of Science:
- Cardiology
- Immunology
- Biochemistry
Background:
- Interleukin-6 (IL-6) exhibits negative inotropic effects.
- Elevated cytokine levels are observed in heart failure patients with reduced ejection fraction.
- Previous studies often focused on compensated chronic heart failure.
Purpose of the Study:
- To investigate the temporal changes in C-reactive protein (CRP) and cytokine concentrations.
- To study patients with cardiomyopathy and acute cardiac decompensation.
- To exclude infection and unstable angina as confounding factors.
Main Methods:
- Measured circulating concentrations of CRP, IL-4, and IL-6.
- Studied eight patients with acute cardiac decompensation.
- Included eight age-matched healthy controls.
Main Results:
- CRP, IL-4, and IL-6 levels were elevated during acute decompensation.
- These markers significantly decreased with symptom resolution (p < 0.05).
- A positive correlation was found between peak CRP and peak IL-6.
Conclusions:
- CRP, IL-4, and IL-6 increase in acute left heart decompensation.
- Levels normalize as heart failure symptoms improve.
- Distinguishing compensated from decompensated states is crucial for interpreting cytokine and acute-phase protein significance in heart failure pathogenesis.
Background:
Interleukin (IL)-6 has recently been shown to have negative inotropic effects, and several studies have reported increases in circulating concentrations of this cytokine in patients with depressed left ventricular ejection fraction and chronic left heart failure. However, most previous clinical studies have measured cytokines in compensated chronic heart failure.
Hypothesis:
The purpose of this study was to examine the temporal evolution of circulating concentrations of C-reactive protein (CRP) and cytokines in patients with cardiomyopathy and acute cardiac decompensation, free of infection and unstable angina.
Methods:
The time course of circulating concentrations of CRP, an anti-inflammatory cytokine interleukin (IL)-4, and a proinflammatory cytokine IL-6 were studied in eight patients with cardiomyopathy and acute cardiac decompensation in the absence of infection or unstable angina. Control samples were obtained from eight age-matched asymptomatic subjects.
Results:
Increased circulating concentrations of CRP (2.6 +/- 0.8 mg/dl), IL-4 (164.6 + 36.5 pg/ml), and IL-6 (17.1 +/- 5.1 pg/ml) were found in all eight patients during acute cardiac decompensation; these values decreased significantly with the resolution of symptoms of cardiac decompensation (0.5 +/- 0.1 mg/dl, 77.8 +/- 23.6 pg/ml, 2.3 +/- 0.1 pg/ml, respectively, p < 0.05 for both). There was a significant correlation between peak CRP and peak IL-6 (p < 0.05).
Conclusions:
In patients with acute left heart decompensation in the absence of infection or coronary events, CRP, IL-4, and IL-6 increased and returned toward normal levels as the symptoms of heart failure resolved. Since the changes in concentrations of CRP, IL-4, and IL-6 in patients with heart failure are dynamic, the distinction between compensated and decompensated state is important when discussing the significance of acute reactive proteins or cytokines in the pathogenesis of heart failure.
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