Estimation of Kinetic Glomerular Filtration Rate in Patients with Decompensated heart Failure

pp. 131-135

Abstract

Background: The coexistence of decompensated heart failure (DHF) and acute renal failure (ARF) is associated with longer hospital stay and greater mortality.

Objectives: The aim of this study was to evaluate whether kinetic glomerular filtration rate (KeGFR) estimated with Chen’s equation can predict the development of ARF or mortality during hospitalization in patients with DHF.

Methods: We conducted a retrospective study of consecutive patients with estimated kinetic glomerular filtration rate using serum creatinine levels on admission and at 24 hours. The primary endpoint was a composite of ARF or mortality, and a ROC curve was built to find the cutoff value with the best sensitivity and specificity to predict events. Acute renal failure was defined according to the KDIGO guideline. Patients were followed-up throughout hospitalization and those with a history of chronic renal failure were excluded from the study.

Results: Among 813 patients, 190 were excluded due to chronic renal failure and 608 patients were analyzed. Median age was 81 years (IQR 25-75%: 73-87) and 48% were men; 25.5% were diabetics, 76% had hypertension, 19.4% had history of prior myocardial infarction and 46.8% presented left ventricular systolic dysfunction defined as left ventricular ejection fraction <45%. Median creatinine level on admission was 1.05 mg/dl. The incidence of the composite event was 41.1%. Age, sex and comorbidities were similar in patients with and without the composite event, but KeGFR was significantly lower in this group of patients (median: 50.7 ml/min vs. 57.9 ml/min, p<0.01) and resulted an independent predictor of mortality. The analysis of the ROC curve revealed that a cutoff point of 60 ml/kg/min for KeGFR (AUC 0.60) had the best diagnostic accuracy to predict the composite event and was present in 58.9% of the patients. Age, female sex, hypertension and diabetes were predictors of the composite event.

Conclusions: Kinetic glomerular filtrate rate can be used as an independent predictor of the composite event, but has no clinical relevance due to its low specificity.