title: Complement C3a predicts outcome in cardiac resynchronization therapy of heart failure.
abstract: BACKGROUND
  The chronic inflammation plays an important role in heart failure and complement components might be useful markers of the prognosis. We set out to evaluate their predictive value in the clinical outcomes of patients with cardiac resynchronization therapy (CRT).
  
  
  METHODS
  We determined the complement levels C3, C3a, sC5b-9 and also the N-terminus of the prohormone brain natriuretic peptide (NT-proBNP) of 126 heart failure patients in a prospective, single-center observational study before and 6 months after CRT implantation.
  
  
  RESULTS
  CRT reduced the C3a [212.5 (148.2-283.6) vs. 153 (119.8-218.3) ng/mL, p < 0.0001] and the sC5b-9 levels [296.9 (234.2-358.8) vs. 255.1 (210.1-319.0) ng/mL, p = 0.0006], but not the total C3 levels [1.43 (1.26-1.61) vs. 1.38 (1.23-1.57) g/L, p = 0.57]. C3a predicted the 5-year mortality of the patients [C3a > 165 ng/mL hazard ratio = 4.21 (1.65-10.72), p = 0.003] independent of the NT-proBNP and other factors. After reclassification, we observed a significant net reclassification improvement [NRI = 0.71 (0.43-0.98), p < 0.0001] and integrated discrimination improvement [IDI = 0.08 (0.03-0.12), p = 0.0002].
  
  
  CONCLUSIONS
  In patients with CRT, elevated C3a levels increase the risk of mortality independent of the NT-proBNP levels or other factors. CRT exerts anti-inflammatory effect by reducing the complement activation.
authors: Heart and Vascular Center, Semmelweis University, Városmajor utca 68, Budapest, 1122, Hungary.
authors: Gábor
authors: G
authors: Széplaki
authors: Heart and Vascular Center, Semmelweis University, Városmajor utca 68, Budapest, 1122, Hungary.
authors: András Mihály
authors: AM
authors: Boros
authors: Heart and Vascular Center, Semmelweis University, Városmajor utca 68, Budapest, 1122, Hungary.
authors: Szabolcs
authors: S
authors: Szilágyi
authors: Heart and Vascular Center, Semmelweis University, Városmajor utca 68, Budapest, 1122, Hungary.
authors: István
authors: I
authors: Osztheimer
authors: Third Department of Internal Medicine, Semmelweis University, Budapest, Hungary.
authors: Zsigmond
authors: Z
authors: Jenei
authors: Heart and Vascular Center, Semmelweis University, Városmajor utca 68, Budapest, 1122, Hungary.
authors: Annamária
authors: A
authors: Kosztin
authors: Heart and Vascular Center, Semmelweis University, Városmajor utca 68, Budapest, 1122, Hungary.
authors: Klaudia Vivien
authors: KV
authors: Nagy
authors: Heart and Vascular Center, Semmelweis University, Városmajor utca 68, Budapest, 1122, Hungary.
authors: Júlia
authors: J
authors: Karády
authors: Heart and Vascular Center, Semmelweis University, Városmajor utca 68, Budapest, 1122, Hungary.
authors: Levente
authors: L
authors: Molnár
authors: Heart and Vascular Center, Semmelweis University, Városmajor utca 68, Budapest, 1122, Hungary.
authors: Tamás
authors: T
authors: Tahin
authors: Heart and Vascular Center, Semmelweis University, Városmajor utca 68, Budapest, 1122, Hungary.
authors: Endre
authors: E
authors: Zima
authors: Heart and Vascular Center, Semmelweis University, Városmajor utca 68, Budapest, 1122, Hungary.
authors: László
authors: L
authors: Gellér
authors: Third Department of Internal Medicine, Semmelweis University, Budapest, Hungary.
authors: Zoltán
authors: Z
authors: Prohászka
authors: Heart and Vascular Center, Semmelweis University, Városmajor utca 68, Budapest, 1122, Hungary. merkely.bela@kardio.sote.hu.
authors: Béla
authors: B
authors: Merkely
mesh_terms: D000368:Aged; D058406:Cardiac Resynchronization Therapy; D003167:Complement Activation; D003165:Complement System Proteins / Q000032:analysis*; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000401:mortality / Q000628:therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*
chemical_list: D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D003165:Complement System Proteins
keywords: C3a; CRT; Reverse remodeling; Survival; sC5b-9