Clinical meaning
Emergency department evaluation of syncope focuses on two questions: (1) Is there a dangerous underlying cause (cardiac syncope)? (2) Can the patient be safely discharged or does admission required? Several validated risk stratification tools assist: The San Francisco Syncope Rule (SFSR) uses the mnemonic CHESS: Congestive heart failure history, Hematocrit <30%, ECG abnormality (new or non-sinus rhythm), Shortness of breath, and Systolic BP <90 at any time. Any single positive criterion identifies patients at risk for serious outcomes within 30 days (sensitivity ~96%, specificity ~62%). The Canadian Syncope Risk Score (CSRS) provides more granular risk stratification using clinical, ECG, and ED variables: heart disease history, elevated troponin, abnormal QRS axis, QTc >480 ms, ED diagnosis of vasovagal syncope (protective, subtracts from score), and ED diagnosis of cardiac syncope. The EGSYS score (Evaluation of Guidelines in SYncope Study) differentiates cardiac from non-cardiac syncope: palpitations before syncope (+4), abnormal ECG or heart disease (+3), syncope during effort (+3), syncope while supine (+2), preceded by autonomic prodromes (nausea, warmth — minus 1), preceded by predisposing/precipitating factors (minus 1). Score ≥3 suggests cardiac etiology. The emergency evaluation includes: detailed history (most important), 12-lead ECG (mandatory), orthostatic vital signs, basic labs (glucose, hemoglobin, troponin if cardiac suspected), and echocardiography if structural heart disease is suspected. CT head and EEG are NOT routinely indicated for syncope — they are indicated only when seizure, stroke, or SAH is suspected based on clinical features.