Changes in Plasma N-Terminal proBNP Levels and Ventricular Filling Pressures During Intensive Unloading Therapy in Elderly With Decompensated Congestive Heart Failure and Preserved Left Ventricular Systolic Function

Abstract

Background Plasma B-type natriuretic peptide (BNP) levels depend on left ventricular (LV) filling pressures and correlate with the state of neurohormonal modulation in patients with congestive heart failure (CHF). In these subjects, therapy of decompensated CHF can determine acute changes in BNP levels. Methods and Results We defined the sequential pattern of N-terminal (T) proBNP in elderly with decompensated CHF and preserved LV systolic function undergoing intensive unloading therapy, assessed the prevalence of patients who significantly reduced NTproBNP at the end of treatment, and verified the relations between changes in NTproBNP and ventricular filling pressures. NTproBNP was measured in 30 patients hospitalized for worsening CHF with LV ejection fraction >50% at admission and after 2 to 4 and 6 to 8 days from the start of treatment. Patients who exhibited a reduction in NTproBNP >35% from baseline to 8-day evaluation were defined as “responders.” Twelve healthy subjects matched for age and sex were used as controls. NTproBNP was significantly higher in CHF patients than controls in all time points, to a greater extent in baseline evaluation (2982 [lower/upper quartile 1273/8146] versus 235 [150/280] pg/mL). A progressive, linear reduction of NTproBNP was detected in CHF patients during unloading. At Day 8, 18 patients (60%) resulted in “responders,” whereas 12 (40%) were “nonresponders.” The former could be predicted through higher pulmonary artery wedge pressure at baseline. Surprisingly, ventricular filling pressures similarly declined in responders and non responders. At Day 8, NTproBNP was yet 7-fold higher in CHF patients than controls. Conclusion Intensive unloading therapy is associated with a significant short-term reduction in NTproBNP in elderly with CHF and preserved LV systolic function. This behavior is progressive and linear during the first week and parallels a reduction in ventricular filling pressures which, however, does not differ between patients who significantly reduce NTproBNP and those who do not. Thus the short-term changes in NTproBNP during intensive unloading therapy in our patients do not depend only on the acute improvement in hemodynamic conditions.