EM · Syncope (approach)
Syncope — the emergency department approach and risk stratification
Also known as Fainting · Blackout · Transient loss of consciousness · Collapse
Syncope — the transient loss of consciousness from the cerebral hypoperfusion, the classification (the reflex, the orthostatic, the cardiac, the cerebrovascular), the critical cardiac-versus-non-cardiac distinction, the San Francisco Syncope Rule for the risk stratification, the ESC high-risk features, the investigation strategy (the ECG, the glucose, the bedside echo), the management (the treat-the-cause, the admission for the high-risk, the discharge with the advice for the low-risk), and the syncope-versus-seizure differential. ACEM-primary, globally tagged.
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Red flags
- A syncope on exertion, a syncope with a chest pain, or a syncope with a palpitation is a cardiac syncope until proven otherwise — these patients need the cardiology and the monitoring
- An abnormal ECG (a conduction abnormality, a prolonged QT, a Brugada pattern, an ischaemia, a ventricular arrhythmia) after a syncope is a high-risk feature mandating the admission
- A family history of a sudden cardiac death at a young age, combined with a syncope, is a high-risk presentation — the cardiology is involved early
- The elderly patient with a syncope may have a serious underlying cause even if the presentation seems benign — the threshold for the workup is lower
- The recurrent syncope in the older patient may be the carotid sinus hypersensitivity — a removable carotid sinus massage (in the monitored setting, no bruit, no stroke history) reproduces the syncope
Meet the patient
A 58-year-old man is brought in after collapsing while climbing a flight of stairs. He recovered fully within thirty seconds and has no chest pain, but he felt a brief palpitation just before he went down. His father died suddenly at fifty. His 12-lead ECG shows a bifascicular block.[1]
One question decides his disposition: is this a cardiac syncope? It is — exertional, with a palpitation, a family history of sudden death, and an abnormal ECG. The error that kills is not missing a rare diagnosis; it is sending home a patient with a cardiac syncope who arrests on the way out. In the Framingham cohort, cardiac syncope doubled the adjusted risk of death from any cause (hazard ratio 2.01 versus participants without syncope).[7]
References11ShowHide
- [1]Goldberger ZD, Petek BJ, Brignole M, et al. ACC/AHA/HRS Versus ESC Guidelines for the Diagnosis and Management of Syncope: JACC Guideline Comparison J Am Coll Cardiol, 2019.PMID 31699282
- [2]Quinn JV, Stiell IG, McDermott DA, et al. Derivation of the San Francisco Syncope Rule to predict patients with short-term serious outcomes Ann Emerg Med, 2004.PMID 14747812
- [3]Brignole M, Moya A, de Lange FJ, et al. 2018 ESC Guidelines for the diagnosis and management of syncope Eur Heart J, 2018.PMID 29562304
- [4]Shen WK, Sheldon RS, Benditt DG, et al. 2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society Circulation, 2017.PMID 28280231
- [5]Sun BC, Mangione CM, Merchant G, et al. External validation of the San Francisco Syncope Rule Ann Emerg Med, 2007.PMID 17210201
- [6]Thiruganasambandamoorthy V, Sivilotti MLA, Le Sage N, et al. Multicenter Emergency Department Validation of the Canadian Syncope Risk Score JAMA Intern Med, 2020.PMID 32202605
- [7]Soteriades ES, Evans JC, Larson MG, et al. Incidence and prognosis of syncope N Engl J Med, 2002.PMID 12239256
- [8]Thiruganasambandamoorthy V, Stiell IG, Sivilotti MLA, et al. Predicting Short-term Risk of Arrhythmia among Patients With Syncope: The Canadian Syncope Arrhythmia Risk Score Acad Emerg Med, 2017.PMID 28791782
- [9]Reed MJ, Newby DE, Coull AJ, et al. The ROSE (risk stratification of syncope in the emergency department) study J Am Coll Cardiol, 2010.PMID 20170806
- [10]Reed MJ, Henderson SS, Newby DE, et al. One-year prognosis after syncope and the failure of the ROSE decision instrument to predict one-year adverse events Ann Emerg Med, 2011.PMID 21288597
- [11]Suh EH, Winskill C, Sacco DL, et al. Validation of 2 Syncope Risk Scores and Comparison With Physician Risk Estimation JAMA Network Open, 2026.PMID 42154462