Abstracts

Abstract

Theaim was to evaluate the effect of renal dysfunction on a plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels and a prognostic impact of NT-proBNP and estimated glomerular filtration rate (eGFR) in patients with heart failure (HF). Methods: 84 patients (mean age 54±8.1 years, 89.3% males) with impaired systolic function (LVEF<40%) and symptomatic HF (NYHA class II-IV) were recruited. During the study patients were treated by optimal medical therapy according to the national guidelines. NT-proBNP levels were measured by CARDIAC proBNP assay with a measurement range from 60 to 3000 pg/ml. Renal function was classified into 6 categories (≥90, 60-89, 45-59, 30-44, 15-29, and <15 mL/min/1.73 m2) by eGFR using the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) formula. Serial blood samples were obtained at baseline. The primary end point was defined as unplanned hospitalization due to HF or death related to HF decompensation. Results: During the follow-up time (follow-up median 18 months), 33 patients (39%) had primary end point (33 hospitalizations due to HF including 6 lethal cases). eGFR (p<0.001), creatinine (p<0.001), NT-proBNP (p<0.001) levels differed significantly between groups. NT-proBNP levels increased with a decrease eGFR. We analyzed the end point onset frequency depending on the NT-proBNP level and eGFR. Analysis of the NT-proBNP concentration and eGFR in relation to clinical condition of patients revealed that 33 patients had primary end point. 16 of these patients had NT-proBNP level more than 3000 pg/ml at baseline visit. 25 patients had eGFR less than 45 mL/min/1.73 m2 and frequency end points increased with a decrease eGFR (p=0.001). We investigated the OR of adverse events depending on NT-proBNP plasma level and eGFR. NT-proBNP level higher 3000 pg/ml at baseline increases the OR of end point onset (OR 95% 2.8 (1.1 - 7.0), p=0.033). eGFR from 45 to 59 mL/min/1.73 m2 increases the OR of end point onset (OR 95% 2.6 (1.03 - 6.34), p<0.044) and eGFR from 30 to 44 mL/min/1.73 m2 increases the OR of end point onset several more (OR 95% 5.8 (1.09 - 30.6), p<0.004). Conclusion: Renal dysfunction increases the concentrations of NT-proBNP. Utilization of the effect of renal dysfunction and NT-proBNP may improve interpretation for diagnosis and monitoring. This strategy allows identify high-risk patients for more intensive monitoring and more aggressive therapy.