NT-pro-BNP for differential diagnosis in patients with syncope.

BACKGROUND

Syncope is a frequent diagnosis and establishing the etiology is often elaborate. Aim of this study was to evaluate the diagnostic value of NT-pro-BNP in patients with syncope.

METHODS

NT-pro-BNP was assessed in 61 patients admitted for syncope to our cardiological department of the University hospital Cologne, Germany.

RESULTS

16 patients (26.2%) had neurally-mediated syncope, 9 (14.8%) had orthostatic syncope, 12 (19.7%) had cardiac arrhythmias, 8 (13.1%) had structural cardiac/cardiopulmonary disease, 2 patients (3.3%) had cerebrovascular disease, 3 (4.9%) had non-syncopal attack and in 11 (18%) patients the cause remained unknown. Patients with cardiac syncope had significantly higher NT-pro-BNP values (514 IQR 286-1154 pg/ml) than patients with non-cardiac cause (182 IQR 70-378 pg/ml, p=0.001). NT-pro-BNP at a cut-off of 164 pg/ml identified patients with cardiac syncope and patients requiring interventional cardiological therapy with a sensitivity of 90% and 93.8%, a specificity of 48.8% and 46.7% and a negative predictive value of 91% and 95.5%. NT-pro-BNP pre-testing could save 45% of the Holter ECGs, 83% of the telemetry monitoring, 47% of stress tests, 49% of echocardiographies, 67% of coronary angiographies and 43% of electrophysiological examinations.

CONCLUSIONS

NT-pro-BNP assessment was helpful in differentiating cardiac from non-cardiac syncope. Further studies are needed to define the role of NT-pro-BNP in the diagnostic algorithm of syncope.