problems with the stability of samples collected

Rationale: Heart Failure (HF) elevated prevalence in Brasil and the world; 20-30% AHF patients develop CardioRenal Syndrome (CRS) type 1; Worsening Renal Failure (WRF) is a prognostic marker of mortality in Acute HF;NGAL is a novel biomarker of Acute Kidney Injury released in 2 hours, and addressed in several different clinical scenarios(contrast injury, cardiopulmonary bypass, critical illness.

Hypothesis: Admission NGAL predicts CRS in AHF patients admitted to the Emergency Room (ER).

Primary goal: To evaluate the diagnostic accuracy and the best cutoff value of urinary NGAL to predict the development of CRS type 1 in patients admitted to the Emergency Room.

Secondary goals: 1- To evaluate the prognostic impact of NGAL on in-hospital adverse outcomes (length of hospitalization, death, institution of renal replacement therapy, use of vasoactive drugs, mechanical ventilation).2- Evaluate the prognostic impact of NGAL in adverse outcomes in 30 days, 60 days and 6 months (death, rehospitalization, institution of renal replacement therapy).3- Identify clinical and hemodynamic characteristics of Acute HF that can influence the evolutionary behavior of NGAL levels in 48 hours.4- Identify the association of drugs commonly used for HF management, which might influence the evolutionary behavior of NGAL levels in 48 hours.5-Assess the impact of NGAL results in clinical decision making.

Methods: Observational, prospective, blinded study. Population: Acute HF patients admitted to the ER of Hospital Pró Cardiaco and Hospital Antonio Pedro - Universidade Federal Fluminense.

Statistics: Convenience Sample size (n=180); determination of best cut-off: ROC analysis; Predictive performance of the cut-off: sensibility, specificity, likelihood ratio, predictive value, accuracy; Identification of variables to predict CRS: logistic regression and square-Qui test; Correlations analysis of normally distributed variables: Pearson's linear correlation test; Mean values for normally distributed variables: Mann-Wittney test; Significance on p<0,05; Intra-assay variation analysis.

Study chronogram: Recruitment: 12 months; Results analysis and conclusions: 60 days; Manuscript preparation for paper submission: 30 days.

Rationale: Heart Failure (HF) elevated prevalence in Brasil and the world; 20-30% AHF patients develop CardioRenal Syndrome (CRS) type 1; Worsening Renal Failure (WRF) is a prognostic marker of mortality in Acute HF; available biomarker shows irreversible damage, late in CRS evolution.(creatinine);NGAL is a novel biomarker of Acute Kidney Injury released in 2 hours, and addressed in several different clinical scenarios(contrast injury, cardiopulmonary bypass, critical illness...); Acute HF patient's risk stratification will allow appropriate resource allocation and establishment of criteria for hospital admission and discharge.

Hypothesis: Admission NGAL predicts CRS in AHF patients admitted to the Emergency Room (ER).

Primary goal: To evaluate the diagnostic accuracy and the best cutoff value of urinary NGAL to predict the development of CRS type 1 in patients admitted to the Emergency Room.

Secondary goals: 1- To evaluate the prognostic impact of NGAL on in-hospital adverse outcomes (length of hospitalization, death, institution of renal replacement therapy, use of vasoactive drugs, mechanical ventilation).2- Evaluate the prognostic impact of NGAL in adverse outcomes in 30 days, 60 days and 6 months (death, rehospitalization, institution of renal replacement therapy).3- Identify clinical and hemodynamic characteristics of Acute HF that can influence the evolutionary behavior of NGAL levels in 48 hours.4- Identify the association of drugs commonly used for HF management, which might influence the evolutionary behavior of NGAL levels in 48 hours.5-Assess the impact of NGAL results in clinical decision making.

Methods: Observational, prospective, blinded study. Population: Acute HF patients admitted to the ER of Hospital Pró Cardiaco and Hospital Antonio Pedro - Universidade Federal Fluminense.

Statistics: Convenience Sample size (n=180); determination of best cut-off: ROC analysis; Predictive performance of the cut-off: sensibility, specificity, likelihood ratio, predictive value, accuracy; Identification of variables to predict CRS: logistic regression and square-Qui test; Correlations analysis of normally distributed variables: Pearson's linear correlation test; Mean values for normally distributed variables: Mann-Wittney test; Significance on p<0,05; Intra-assay variation analysis.

Study chronogram: Recruitment: 12 months; Results analysis and conclusions: 60 days; Manuscript preparation for paper submission: 30 days.

Inclusion Criteria:

• acute heart failure according to the Framingham's criteria
• informed consent signed

Exclusion Criteria:

• Acute coronary syndrome
• cardiogenic shock
• terminal renal disease
• transplanted patients
• known nephrotoxicity exposure
• urinary tract infection
• sepsis

Adult patients admitted to the Emergency rooms of Hospital PróCardíaco and Hospital Universitário Antonio Pedro, presenting with acute heart failure according to the Framingham's criteria. The subjects must sign the informed consent term.