Document Type : Original Article


1 Emergency Medicine Department, Imam Hossein Hospital, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran

2 Cardiology Department, Imam Hossein Hospital, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran

3 Road Traffic Injury Research Center, Tabriz University of Medical Sciences, Tabriz, Iran

4 Emergency Medicine Department, Imam Reza Hospital, Birgand University of Medical Sciences, Birgand, Iran

5 Proteomics Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran

6 Emergency Medicine Department, Shohadaye Tajrish Hospital, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran


Objective: The significance of diagnosing the root reason for syncope and taking the
required preventive or treatment measures cannot be overlooked when it comes to
outcome prediction. This study endeavors to examine the role of proBNP in differentiating
cardiogenic and non-cardiogenic syncope in patients presenting to the emergency
department (ED).
Methods: We prospectively performed a cross-sectional study on patients presenting
with acute syncope. All the patients for this investigation were followed up until the
definite cause of their syncope (cardiac or non-cardiac) was diagnosed and the screening
performance characteristics of proBNP in differentiation of cardiogenic and noncardiogenic syncope were evaluated.
Results: Three hundred patients with syncope were studied (64.7% male). In the end,
the cause of syncope was determined to be cardiogenic in 133 cases (44.3%). The area
under the ROC curve of proBNP in the differentiation of cardiogenic syncope from noncardiogenic was estimated to be 78.9 (95% CI: 73.5 – 84.3). The optimal cut-off point for
proBNP in this regard was 143.5 pg/mL point. Sensitivity, specificity, positive and negative
predictive values, and positive and negative likelihood ratios of proBNP in the mentioned
cut-off point were 75.39% (95% CI: 67.61–82.73), 75.44% (95% CI: 68.07–81.62), 71.12%
(95% CI: 62.82–78.26), 79.74% (95% CI: 72.46–85.54), 2.46 (95% CI: 1.86–3.25), and 0.25
(95% CI: 0.18–0.34), respectively.
Conclusion: The accuracy of proBNP in differentiation of cardiogenic and non-cardiogenic
syncope is fair. ProBNP concentration equals to or higher than 143.5 pg/mL can differentiate
cardiogenic syncope from non-cardiogenic with 75% sensitivity and 76% specificity. It
seems that its use for this purpose should be considered with caution and along with other


Main Subjects

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