Canadian Syncope Risk Score effectively rules out the risk of serious outcomes after syncope

Reference

Thiruganasambandamoorthy V, Sivilotti ML, Le Sage N, et al. Multicenter emergency department validation of the Canadian syncope risk score. JAMA Intern Med 2020;180(5):737-744.

Synopsis

This evaluation of the CSRS was conducted on 3819 patients (80.5% of enrolled patients) in 9 emergency departments across Canada. The authors enrolled consecutive patients, 16 years or older, who presented within 24 hours of syncope. The CSRS collects history, blood pressure, troponin level, electrocardiogram result, and clinical diagnosis to predict the risk of a serious adverse event in the subsequent 30 days. However, electrocardiogram was not performed in 3% of patients, and 41% did not have troponin measured. Outcomes were assessed through medical record and health utilization database analysis and telephone follow-up to each patient. Two 2 emergency physicians who were masked to the score determined the outcomes. Of the analyzed patients, 13 deaths (0.3%) occurred and serious outcomes occurred in 3.6% within 30 days; most of these (2.8% of all patients) were arrhythmias. A total of 0.3% of patients at very low risk and 0.7% of patients at low risk experienced a serious outcome within 30 days, and none died or had a ventricular arrhythmia; at the other end, 51.3% of patients at very high risk experienced a serious outcome. Even in the medium-risk group, arrhythmia outcomes occurred in only 5.8% of patients. Another recent study has shown the addition of N-terminal pro-B-type natriuretic peptide testing does not add to the prognostic ability of the CSRS.