title: Association of BNP and Troponin Levels with Outcome among Cardiac Resynchronization Therapy Recipients.
abstract: BACKGROUND
  We conducted a prospective multicenter study to assess the prognostic value of combined baseline preimplant plasma levels of the biomarkers cardiac troponin T (TnT) and B-type natriuretic peptide (BNP) among cardiac resynchronization therapy (CRT) with or without defibrillator capability (CRT-D) recipients.
  
  
  METHODS
  At CRT-D implant, patients were stratified based on detectable TnT (≥0.01 ng/mL) and elevated BNP (predefined as >440 pg/mL) levels. Patients were classified into three groups: high (both detectable TnT and high BNP), intermediate (either detectable TnT or high BNP), or low (nondetectable TnT and low BNP). Patients were followed for 12 months. Survival curves free from mortality or heart failure hospitalizations (HFH) were assessed. To assess the predictive value of biomarker category, we constructed a multivariate Cox regression model, including the covariates of age, New York Heart Association class, left ventricular ejection fraction (LVEF), and QRS duration.
  
  
  RESULTS
  A total of 267 patients (age 66 ± 12 years, males 80%, LVEF 25% ± 8%, ischemic cardiomyopathy 52%, QRSd 155 ± 26 ms) were studied. After 1 year, there were 13 deaths and 25 HFH events. A significant difference in event-free survival among the three groups was observed, with high and intermediate categories having worse survival than low (log-rank test, P < 0.001). In the multivariate model, risk category was a significant predictor of outcome: hazard ratios were 7.34 (95% confidence interval [CI]: 2.48-21.69) and 2.50 (95% confidence interval [CI]: 1.04-6.04) for high-risk and intermediate-risk groups, respectively (P < 0.0001).
  
  
  CONCLUSIONS
  Among CRT-D recipients, baseline TnT and BNP values alone or in combination provide significant prognostic value for the outcome of mortality or HFH.
authors: University of Pittsburgh, Pittsburgh, Pennsylvania; VA Pittsburgh Healthcare System, Pittsburgh, Pennsylvania.
authors: Alaa A
authors: AA
authors: Shalaby
authors: William T
authors: WT
authors: Abraham
authors: Gregg C
authors: GC
authors: Fonarow
authors: Malcolm M
authors: MM
authors: Bersohn
authors: John
authors: J
authors: Gorcsan
authors: Li-Yin
authors: LY
authors: Lee
authors: Jasmina
authors: J
authors: Halilovic
authors: Samir
authors: S
authors: Saba
authors: Alan
authors: A
authors: Maisel
authors: Jagmeet P
authors: JP
authors: Singh
authors: Ali
authors: A
authors: Sonel
authors: Alan
authors: A
authors: Kadish
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D058406:Cardiac Resynchronization Therapy; D009202:Cardiomyopathies / Q000503:physiopathology / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D016019:Survival Analysis; D016896:Treatment Outcome; D014336:Troponin / Q000097:blood*
chemical_list: D015415:Biomarkers; D014336:Troponin; D020097:Natriuretic Peptide, Brain
keywords: BNP; biomarkers; cardiac resynchronization therapy; congestive heart failure; troponin