San Francisco Syncope Rule
Identifies high-risk syncope patients requiring urgent evaluation. Mnemonic: CHESS.
How to use & interpret
The San Francisco Syncope Rule screens for short-term (7-day) serious outcomes after an episode of syncope, using the CHESS criteria: history of Congestive heart failure, Haematocrit <30%, abnormal ECG, Shortness of breath, and Systolic BP <90 mmHg.
If none are present, the risk of a serious outcome is low; any positive criterion identifies a higher-risk patient who generally warrants further assessment or admission. It is a sensitive rule-out aid, not a rule-in test, and works best combined with clinical judgement.
Score interpretation
No high-risk features. Low risk for serious 7-day outcome.
→ Consider discharge with appropriate follow-up.
≥1 high-risk feature present. Increased risk of serious adverse event within 7 days.
→ Admit for further evaluation and monitoring.
Interpretation bands for the SFSR. Apply clinical judgement and local guidance.
Frequently asked questions
Does a negative San Francisco Syncope Rule mean I can discharge?
It supports a low-risk assessment, but disposition still depends on the overall clinical picture, the suspected cause, comorbidity and social factors.
References
- Quinn JV et al. A prospective investigation of the San Francisco Syncope Rule. Ann Emerg Med. 2004;43(2):224-232.
Related
Curated clinical cross-links plus same-class fallbacks.
- Labetalol (IV — Hypertensive Emergency) · Combined Alpha-1 and Beta-Adrenergic Blocker
- Lidocaine IV (Cardiac Arrhythmia) · Antiarrhythmic
- Protamine Sulphate (Heparin Reversal) · Heparin Reversal / Cardiac Surgery
- Mavacamten · Cardiac myosin inhibitor
- Labetalol (IV — Hypertensive Emergency) · Combined alpha and beta blocker
- Tenecteplase · Cardiovascular Emergency
- Acute Heart Failure · ESC 2021 Heart Failure Guidelines; NICE NG106
- NSTEMI / Unstable Angina · ESC 2020 NSTEMI Guidelines; NICE NG185
- New-Onset Atrial Fibrillation · ESC 2020 AF Guidelines; NICE NG196
- Hypertensive Emergency · ESC/ESH 2018 Hypertension Guidelines; NICE NG136
- Bradycardia Management · Resuscitation Council UK ABCDE; ESC 2021 Pacing Guidelines
- Ventricular Tachycardia / Fibrillation · Resuscitation Council UK ACLS; ESC 2022 Ventricular Arrhythmia Guidelines
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.