Accuracy of bioimpedance vector analysis and brain natriuretic peptide in detection of peripheral edema in acute and chronic heart failure

OBJECTIVE: To evaluate the role of bioelectrical impedance vector analysis (BIVA) and brain natriuretic peptide (BNP) in detecting peripheral congestion in heart failure (HF). BACKGROUND: BIVA/BNP are biomarkers for congestion in acute (ADHF) and chronic HF. METHODS: 487 ADHF and 413 chronic HF patients underwent BIVA and BNP tests. RESULTS: BIVA was more accurate than BNP in detecting peripheral congestion both in ADHF (AUC 0.88 vs 0.57 respectively; p < 0.001) and chronic HF patients (AUC 0.89 vs 0.68, respectively; p < 0.001). In ADHF patients, the optimal BNP cut-off for discriminating presence or absence of edema was >870 pg/mL (PPV = 48% and NPV = 58%) whereas in chronic HF it was >216 pg/mL (PPV = 18% and NPV = 95%). The BIVA detected edema when the vector fell into the lower pole of 75th percentile tolerance ellipse (PPV = 84% and NPV = 78%) in ADHF, the lower pole of 50% (PPV = 68% and NPV = 95%) in chronic HF. CONCLUSIONS: In HF patients, BIVA is an easy, fast technique to assess peripheral congestion, and is even more accurate than BNP.