Use of N terminal Pro Brain Natriuretic Peptide (NTproBNP) for assessment of risk of contrast induced nephropathy (CIN) in patients undergoing elective percutaneous coronary intervention (PCI)

Abstract

Purpose: The clinical variables associated with the development of CIN are advanced age, diabetes mellitus, prior myocardial infarction, impaired left ventricular function, cardiogenic shock and renal dysfunction. A risk score has been proposed by Mehran et al for prediction of CIN. We studied the additive value of pre-procedure NTproBNP to Mehran risk score in prediction of CIN in patients undergoing PCI. Methods: We recruited 127 consecutive patients undergoing elective PCI meeting the inclusion criteria. The high risk was defined as one of the following criteria - age >70 years, diabetes mellitus, serum creatinine >2 mg/dl or GFR <45 ml/min, LVEF <35% or grade III or IV diastolic dysfunction, presence of peripheral vascular disease, prior revascularisation, recent ACS with raised Troponin T. The criteria for contrast induced nephropathy was composite rise in the serum creatinine level of more than 25% or absolute rise of 0.5 mg/dl at 48 hours or with a reduction in urine output to less than 0.5 mL/kg/hour for 6 hours after PCI. The data was analysed using standard statistical methods and compared using Students T test. Results: Of 127 patients recruited, 26 developed CIN (20.47%). The mean age, baseline serum creatinine, eGFR and Mehran risk score was similar between those who developed CIN (CIN positive) and who did not (CIN negative). The LVEF was significantly lower in CIN positive patients as compared to the other group (40.65385±13.72572 vs 45.93069±15.04876, p value 0.05366). The mean NT pro BNP level 3158 pg/L in those who developed CIN as compared to other group 1698 pg/L (p value 0.05). Table 1. Table comparing baseline characteristics of the groups Conclusions: The pre-procedure NT PRO BNP level and baseline LV function assessments has incremental value in identifying patients at high risk of CIN over Mehran risk score.