Tehran University of Medical Sciences The Research in Heart Yield and Translational Medicine (RHYTHM) 3115-7270 15 2 2020 04 30 57 63 EN Yaser Jenab Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Ali-Mohammad Haji-Zeinali Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Mohammad Javad Alemzadeh-Ansari Cardiovascular Intervention Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Shapour Shirani Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Mojtaba Salarifar Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Mohammad Alidoosti Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Hamed Vahidi Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Marzieh Pourjafari Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Arash Jalali Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. 2018 11 16 2020 01 18 Background: In patients with heart failure, elevated levels of blood urea nitrogen (BUN) is a prognostic factor. In this study, we investigated the prognostic value of elevated baseline BUN in short-term mortality among patients with acute pulmonary embolism (PE). Methods: Between 2007 and 2014, cardiac biomarkers and BUN levels were measured in patients with acute PE. The primary endpoint was 30-day mortality, evaluated based on the baseline BUN (≥14 ng/L) level in 4 groups of patients according to the European Society of Cardiology’s risk stratification (low-risk, intermediate low-risk, intermediate high-risk, and high-risk). Results: Our study recruited 492 patients with a diagnosis of acute PE (mean age=60.58±16.81 y). The overall 1-month mortality rate was 6.9% (34 patients). Elevated BUN levels were reported in 316 (64.2%) patients. A high simplified pulmonary embolism severity index (sPESI) score (OR: 5.23, 95% CI: 1.43–19.11; P=0.012), thrombolytic or thrombectomy therapy (OR: 2.42, 95% CI: 1.01–5.13; P=0.021), and elevated baseline BUN levels (OR: 1.04, 95% CI: 1.01–1.03; P=0.029) were the independent predictors of 30-day mortality. According to our receiver-operating characteristics analysis for 30-day mortality, a baseline BUN level of greater than 14.8 mg/dL was considered elevated. In the intermediate-low-risk patients, mortality occurred only in those with elevated baseline BUN levels (7.2% vs. 0; P=0.008). Conclusion: An elevated baseline BUN level in our patients with PE was an independent predictor of short-term mortality, especially among those in the intermediate-risk group. https://jthc.tums.ac.ir/index.php/jthc/article/view/981 https://jthc.tums.ac.ir/index.php/jthc/article/download/981/901