Prognostic value of NT-proBNP levels in patients undergoing permanent pacemaker implantation.

INTRODUCTION Several reports confirmed the prognostic value of the N-terminal fragment of B-type natriuretic peptide prohormone (NT-proBT) in various patient populations. Patients with medical indications for implantation of an artificial cardiac pacemaker are at high risk of cardiovascular events. There is limited data assessing the prognostic value of NT-proBNP in this group. OBJECTIVES The aim of the study was to establish the prognostic value of NT-proBNP in patients scheduled for the implantation of a cardiac stimulator. PATIENTS AND METHODS The study included 59 patients (average age 79.8 +/-6.3 years) with indications for implantation of a permanent pacemaker. NT-proBNP was measured in each patient on admission and 46 patients had their NT-proBNP measured 1 month after implantation. All patients were followed up for 4 years. We examined the incidence of cardiovascular events as endpoints. Finally, we analyzed the relationship between the initial concentration of NT-proBNP measured on admission and at 1 month and the risk of the occurrence of the endpoint (analysis in the group in whom events occurred vs. group without the endpoint). RESULTS NT-proBNP values at baseline and at 1 month (NT-proBNP1month) were significantly higher in patients who experienced cardiovascular events than in those who were free of such events (NT-proBNP: 2310.6 +/-2657.7 pg/ml vs. 1177.6 +/-1364.6 pg/ml, P <0.2; NT-proBNP1month: 2538 +/-3341.4 pg/ml vs. 1139.4 +/-1294.1 pg/ml, P <0.03, respectively). A cut-off point of the initial NT-proBNP value of 577 pg/ml was estimated as the most accurate prognostic risk factor for cardiovascular events within a 4-year follow-up (sensitivity 77%, specificity 52%). CONCLUSIONS The level of NT-proBNP prior to as well as 1 month after cardiac pacemaker implantation can be useful in identifying patients with higher risk of future cardiovascular events. We suggest using the baseline NT-proBNP concentration of 577 pg/ml as a cut-off value for assessing the risk for such events.