Emergency. 2018; 6 (1): e12 LE T T E R TO ED I TO R Brain Natriuretic Peptides in Screening of Syncope with Cardiac Origin; a Commentary Hamideh Feiz Disfani1, Mostafa Kamandi2∗, Kazem Rahmani3 1. Department of Emergency Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. 2. Department of Internal Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. 3. Department of Epidemiology and Biostatistics, Iran University of Medical Sciences, Tehran, Iran Received: January 2018; Accepted: February 2018; Published online: 18 February 2018 Cite this article as: Brain Natriuretic Peptides in Screening of Syncope with Cardiac Origin; a Commentary. Emergency. 2018; 6(1): e12. Dear Editor: Syncope is a serious problem with life-time prevalence of 35% (1). It is estimated that 1 -3% of referrals to emergency departments and in-patient admissions are due to syncope (2). The underlying conditions can be cardiac or neurologic. Considering the completely different circumstances ruling the encounters with cardiac and neurologic syncope, in re- cent years many attempts have been made to find the proper tool for differentiating cardiac and non-cardiac causes of syncope. The result of which is formation of some clinical decision rules including San Francisco Syncope Rule (SFSR), Osservatorio Epidemiologico sulla Sincope nel Lazio (OE- SIL), Evaluation of Guidelines in Syncope Study (EGSYS), risk stratification of syncope in the emergency department (Rose), and Boston Syncope Rules. The serum marker brain natriuretic peptide (BNP), which is becoming increasingly established in emergency depart- ments for diagnosis of acute heart failure, can reflect the presence of a structural heart disease (3-5). It seems that BNP could be considered as a screening tool in detection of syn- cope with cardiac origin. In a study by Wojtowicz J et al. who evaluated BNP in chil- dren and adolescents with syncope, there was no significant difference in terms of BNP level between the syncope and control groups (6). In contrast, Zhang Q et al. concluded that serum BNP is helpful in differentiating cardiac (958.78 ± 2443.41 pg/mL) and non-cardiac (31.05 ± 22.64 pg/mL) syn- cope (7). Tanimoto K et al. considered the cut-off value of 40 pg/ml for BNP in differentiating cardiac and non-cardiac syncope and ∗Corresponding Author: Mostafa Kamandi; Department of Internal Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. E-mail: mostafaakamandi@gmail.com Tel: 00985138525312 found that it had 82% sensitivity and 92% specificity (8). A significant difference was observed in BNP level of the car- diac group (514 pg/ml) compared to the non-cardiac ones (182 pg/ml) in Pfister et al. study (4). It seems that, more re- search is needed to clarify this relationship and the variables that might play the role of confounders in a causal inference. More studies on children are required because there is some controversy regarding this relationship. Running studies with accurate methodology, large sample sizes, and in a multi- centric fashion could be helpful in this regard. 1. Appendix 1.1. Acknowledgements None. 1.2. Author contribution All authors pass the four criteria for authorship contribution based on the International Committee of Medical Journal Ed- itors (ICMJE) recommendations. 1.3. Funding/Support None. 1.4. Conflict of interest None. References 1. Ganzeboom KS, Mairuhu G, Reitsma JB, Linzer M, Wieling W, Van Dijk N. Lifetime cumulative incidence of syncope in the general population: a study of 549 Dutch subjects aged 35–60 years. Journal of cardiovascular electrophysi- ology. 2006;17(11):1172-6. 2. Kenny RA, Bhangu J, King-Kallimanis BL. Epidemiology of syncope/collapse in younger and older Western pa- This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: www.jemerg.com H. Feiz Disfani et al. 2 tient populations. Progress in cardiovascular diseases. 2013;55(4):357-63. 3. Pfister R, Tan D, Thekkanal J, Hellmich M, Schneider CA. Predictors of elevated NT-pro-BNP in cardiovascular pa- tients without acute heart failure. International journal of cardiology. 2009;131(2):277-80. 4. Costantino G, Solbiati M, Pisano G, Furlan R. NT-pro-BNP for differential diagnosis in patients with syncope. Inter- national journal of cardiology. 2009;137(3):298-9. 5. Tada H, Ito S, Shinbo G, Tadokoro K, Ito I, Hashimoto T, et al. Significance and utility of plasma brain natriuretic peptide concentrations in patients with idiopathic ven- tricular arrhythmias. Pacing and clinical electrophysiol- ogy. 2006;29(12):1395-403. 6. Wojtowicz J, Szczepanski W, Bogdan A, Baran M, Szczu- rak J, Bossowski A. Natriuretic peptides in the evalu- ation of syncope in children and adolescents. Scandi- navian journal of clinical and laboratory investigation. 2014;74(4):301-5. 7. Zhang Q, Jin H, Qi J, Yan H, Du J. Diagnostic value of serum brain natriuretic peptide in syncope in children and ado- lescents. Acta Paediatrica. 2013;102(5). 8. Tanimoto K, Yukiiri K, Mizushige K, Takagi Y, Masug- ata H, Shinomiya K, et al. Usefulness of brain natriuretic peptide as a marker for separating cardiac and noncar- diac causes of syncope. American Journal of Cardiology. 2004;93(2):228-30. This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: www.jemerg.com Appendix References