Effects of hemoglobin concentration and creatinine clearance in pro-B-type natriuretic peptide-based left ventricular filling pressure prediction in patients with preserved left ventricular systolic function

Although N-terminal pro-B-type natriuretic peptide (pro-BNP) has been shown to correlate with left ventricular (LV) filling pressure, pro-BNP-based LV filling pressure prediction has some limitations due to several factors that affect pro-BNP. The aim of this study was to evaluate the effects of blood hemoglobin concentration and creatinine clearance (CCr) on pro-BNP-based LV filling pressure prediction in patients with preserved LV systolic function. A total of 421 consecutive patients referred for coronary angiography underwent LV pressure measurement by fluid-filled catheters. Patients with plasma creatinine levels >= 1.5 mg/dl and LV ejection fractions < 50% were excluded. LV diastolic pressures and echocardiographic parameters were compared with pro-BNP levels in 281 patients. Blood hemoglobin levels and CCr were measured simultaneously. Log pro-BNP was independently correlated with hemoglobin concentration (beta = -0.261, p < 0.001), CCr (P = -0.230, p < 0.001) and LV pre-A-wave pressure (beta = 0.384, p < 0.001). A pro-BNP level of 124 pg/ml was the optimal cutoff for LV pre-A-wave pressure > 15 mm Hg in all patients (sensitivity 67%, specificity 67%, p < 0.001). However, by subclassification according to hemoglobin and CCr tertiles, optimal cut-off values varied significantly, and their predictive accuracies could be improved (from 89 to 331 pg/dl, with diagnostic accuracy up to 79%). In conclusion, in the pro-BNP-based prediction of elevated LV filling pressure, subclassification on the basis of hemoglobin concentration and CCr should be considered in patients with preserved LV systolic and renal function. (c) 2008 Elsevier Inc. All rights reserved.