Does N-terminal pro-brain natriuretic peptide add prognostic value to the Mehran risk score for contrast-induced nephropathy and long-term outcomes after primary percutaneous coronary intervention?

To evaluate the prognostic value of plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) in relation to Mehran risk score (MRS) for contrast-induced nephropathy (CIN) in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We prospectively enrolled 283 consecutive patients treated with PPCI for STEMI. NT-proBNP was measured, and the MRS was calculated. The primary end point was CIN, defined as an absolute increase in serum creatinine aeyen0.5 mg/dL from baseline within 48-72 h after contrast medium exposure. The incidence of CIN was 9.2 %. Patients with CIN had higher NT-proBNP and MRS than those without CIN. The value of NT-proBNP was similar to MRS for CIN (C statistics 0.760 vs. 0.793, p = 0.689). After adjustment for MRS, elevated NT-proBNP (defined as the best cutoff point) was significantly associated with CIN. The addition of elevated NT-proBNP to MRS did not significantly improve the C statistics, over that with the original MRS model (0.833 vs. 0.793, p = 0.256). In addition, similar results were observed for in-hospital and long-term major adverse clinical events. Although NT-proBNP did not add any prognostic value to the MRS model for CIN, NT-proBNP, as a simple biomarker, was similar to MRS, and may be another useful and rapid screening tool for CIN and death risk assessment, identifying subjects who need therapeutic measures to prevent CIN.