Renal Clearance of N-Terminal pro-Brain Natriuretic Peptide Is Markedly Decreased in Chronic Kidney Disease

Background: The ratio of N-terminal pro-brain natriuretic peptide (NT-proBNP) secretion from the heart to peripheral NT-proBNP remains unknown in patients with chronic kidney disease (CKD). Methods and Results: We measured plasma NT-proBNP in the aortic root (AO; NT-proBNP(AO)) and in the coronary sinus (CS; NT-proBNP(CS)) in 544 patients. Patients were classified into 6 categories based on estimated glomerular filtration rate (eGFR): G1, n=44, eGFR ≥90 mL/min/1.73 m(2); G2, n=221, 60≤eGFR<90 mL/min/1.73 m(2); G3a, n=132, 45≤eGFR<60 mL/min/1.73 m(2); G3b, n=77, 30≤eGFR<45 mL/min/1.73 m(2); G4, n=34, 15≤eGFR<30 mL/min/1.73 m(2); and G5, n=36, eGFR <15 mL/min/1.73 m(2). In non-CKD patients, hemodynamics but not eGFR were independent predictors of log NT-proBNP. In CKD patients, eGFR and hemodynamics were independent predictors of log NT-proBNP. The ratio of NT-proBNP secretion from the heart to NT-proBNP(AO) significantly decreased with decreasing eGFR in 6 groups (P<0.0001): G1, 67±38%; G2, 50±24%; G3a, 40±21%; G3b, 30±16%; G4, 14.8±7.9%; and G5, 3.5±2.4%, respectively. Conclusions: eGFR contributes to the value of NT-proBNP for prediction of hemodynamic overload in CKD patients but not in non-CKD patients, and the ratio of NT-proBNP secretion from the heart to peripheral NT-proBNP is markedly decreased in CKD patients, especially those with eGFR <30 mL/min/1.73 m(2).