Impact of troponin I-autoantibodies in chronic dilated and ischemic cardiomyopathy.
The aim of this study was to investigate the prognostic value of circulating troponin I (TNI)-autoantibodies in plasma of patients with chronic heart failure. Sera of 390 heart failure patients were tested for the presence of anti-TNI antibodies by enzyme-linked immunosorbent assay (ELISA), including 249 (63.8% of total) patients with dilated cardiomyopathy (DCM) and 141 (36.2% of total) patients with ischemic cardiomyopathy (ICM). A total of 72 patients (18.5% of total) were female and 318 (81.5% of total) were male. Mean patient age was 54.6 ± 11.3 years and mean follow-up time was 3.8 ± 3.2 years. TNI-autoantibodies (titer of ≥1:40) were detected in 73 out of 390 patients (18.7% of total). In TNI-autoantibody positive patients mean left ventricular ejection fraction (LVEF) was 27.6 ± 5.8%, compared to 25.8 ± 5.9% in TNI-autoantibody negative patients, P = 0.03. The combined end-point of death (n = 118, 30.3% of total) or heart transplantation (HTX) (n = 44, 11.3% of total) was reached in 162 patients (41.5% of total). Kaplan-Meier analysis demonstrated superior survival (combined end-point of death or HTX) in patients with DCM versus ICM (P = 0.0198) and TNI-autoantibody positive patients versus TNI-autoantibody negative patients (P = 0.0348). Further subgroup analysis revealed a favorable outcome in TNI-positive patients with heart failure if the patients suffered from DCM (P = 0.0334), whereas TNI-autoantibody status in patients with ICM was not associated with survival (P = 0.8486). In subsequent multivariate Weibull-analysis, a positive TNI serostatus was associated with a significantly lower all-cause mortality in DCM patients (P = 0.0492). The presence of TNI-autoantibodies in plasma is associated with an improved survival in patients with chronic DCM, but not ICM. This might possibly indicate a prophylactic effect of TNI-autoantibodies in this subgroup of patients, encouraging further studies into possible protective effects of antibodies against certain cardiac target structures.
Department of Cardiology, University of Heidelberg, 69120 Heidelberg, Germany. Andreas.Doesch@med.uni-heidelberg.de
Andreas O
AO
Doesch
Susanne
S
Mueller
Manfred
M
Nelles
Mathias
M
Konstandin
Sultan
S
Celik
Lutz
L
Frankenstein
Stefan
S
Goeser
Ziya
Z
Kaya
Achim
A
Koch
Christian
C
Zugck
Hugo A
HA
Katus
D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood*; D002311:Cardiomyopathy, Dilated / Q000097:blood* / Q000276:immunology / Q000401:mortality; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000209:etiology / Q000401:mortality; D016027:Heart Transplantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D019210:Troponin I / Q000276:immunology*
D001323:Autoantibodies; D019210:Troponin I