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Measuring the 50% Haemolytic Complement (CH50) Activity of Serum
08:26

Measuring the 50% Haemolytic Complement (CH50) Activity of Serum

Published on: March 29, 2010

Serum complement activation in congestive heart failure

D J Clark1, M W Cleman, S E Pfau

  • 1Section of Cardiovascular Medicine, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.

American Heart Journal
|March 29, 2001
PubMed

Insights

Terminal complement activation, measured by C5b-9 levels, is elevated in congestive heart failure (CHF) patients. Higher C5b-9 levels correlate with severe symptoms and adverse clinical outcomes in CHF.

Area of Science:

  • Cardiology
  • Immunology
  • Complement System

Background:

  • Complement system activation is implicated in myocardial injury during myocardial infarction and cardiopulmonary bypass.
  • The role of complement activation in congestive heart failure (CHF) remains largely unknown.

Purpose of the Study:

  • To investigate the presence of terminal complement activation in patients with CHF.
  • To determine the relationship between terminal complement activation and clinical outcomes in CHF patients.

Main Methods:

  • Serum levels of the terminal complement complex C5b-9 were measured in 36 patients with symptomatic heart failure (left ventricular ejection fraction <40%).
  • C5b-9 levels were compared to those of 12 age-matched control subjects.
  • Combined clinical outcomes (death, urgent heart transplantation, or hospitalization for worsening heart failure) were assessed at 6 months.

Main Results:

  • Patients with CHF exhibited significantly higher serum C5b-9 levels (101.5 ng/mL) compared to controls (36.5 ng/mL; P =.003).
  • The highest C5b-9 levels (top 50th percentile) were associated with a higher prevalence of New York Heart Association class IV symptoms (67% vs 33%; P =.04).
  • Patients with the highest C5b-9 levels also experienced significantly more adverse clinical outcomes within 6 months (56% vs 17%; P =.02).

Conclusions:

  • Circulating levels of C5b-9, the terminal complement complex, are significantly elevated in patients with symptomatic heart failure.
  • Elevated C5b-9 levels are associated with increased near-term adverse clinical events in CHF patients.
Abstract

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