Predicting in-hospital mortality in pulmonary embolism patients: development and external validation of the PATHOS score

Objective According to the 2019 European Society of Cardiology (ESC) guidelines on pulmonary embolism (PE), prognosis is calculated using the Pulmonary Embolism Severity Index (PESI), a complex score with debated validity, or simplified PESI (sPESI). We have developed and validated a new risk score for in-hospital mortality (IHM) of patients with PE in the emergency depart-ment.Methods This retrospective, dual-center cohort study was conducted in the emergency depart-ments of two third-level university hospitals. Patients aged > 18 years with a contrast-enhanced computed tomography-confirmed PE were included. Clinical variables and laboratory tests were evaluated blindly to IHM. Multivariable logistic regression was performed to identify the new score's predictors, and the new score was compared with the PESI, sPESI, and shock index.Results A total of 1,358 patients were included in this study: 586 in the derivation cohort and 772 in the validation cohort, with a global 10.6% of IHM. The PATHOS scores were developed using independent variables to predict mortality: platelet count, age, troponin, heart rate, oxy-genation, and systolic blood pressure. The PATHOS score showed good calibration and high dis-crimination, with an area under the receiver operating characteristics curve of 0.83 (95% confi-dence interval [CI], 0.77-0.89) in the derivation population and 0.74 (95% CI, 0.68-0.80) in the validation cohort, which is significantly higher than the PESI, sPESI, and shock index in both co-horts (P< 0.01 for all comparisons).Conclusion PATHOS is a simple and effective prognostic score for predicting IHM in patients with PE in an emergency setting.