Evaluation of NT-proBNP to predict outcomes in advanced heart failure

Abstract

To determine which factors predict outcomes in a group of patients with advanced heart failure, and in particular if NT-proBNP provides additional clinical and prognostic information to other haemodynamic and biochemical data. Ninety-one patients were studied who were being evaluated for heart transplantation, with 166 assessments. The patients had advanced heart failure as determined by median cardiac index of 2.0 l/min/m(2), left ventricular end-diastolic diameter of 7.0 mm and levels of NT-proBNP of 2473 pg/ml. Median follow-up time was 359 days. Clinicians were blinded to NT-proBNP levels. NT-proBNP significantly correlated with cardiac index (R = -0.44, p < 0.001), right atrial pressure (R = 0.40, p < 0.001), pulmonary arterial wedge pressure (R = 0.38, p < 0.001) and albumin (R = -0.52, p < 0.001), and total bilirubin with right atrial pressure (R = 0.59, p < 0.001). Cardiac index was the most important independent predictor of outcome (p = 0.0001), although bilirubin (p = 0.001) and NT-proBNP (p < 0.05) were also significant. In patients with a 50% increase in NT-proBNP, 64% had adverse outcomes, whereas those in whom levels were stable, 22% had adverse outcomes (p < 0.05). Cardiac index is the primary independent predictor of outcome in advanced heart failure when haemodynamic deterioration is evident. In situations where invasive haemodynamics are not available, total bilirubin (reflecting hepatic congestion) and NT-proBNP (related to haemodynamics) also provide important prognostic information.