🫀 San Francisco Syncope Rule
Identify high-risk syncope with the San Francisco Syncope Rule (CHESS).
San Francisco Syncope Rule
History of congestive heart failure
Haematocrit < 30%
Abnormal ECG (new changes / non-sinus)
Shortness of breath
Systolic BP < 90 mmHg at triage
When to use
Predict serious 7-day outcomes after syncope.
How it works
Any of CHF history, Haematocrit < 30%, abnormal ECG, Shortness of breath, SBP < 90 mmHg → high risk.
Key points
- Any positive factor flags higher risk.
- Sensitive but limited specificity.
- Use with clinical judgement and other risk tools.
References
Decision support for licensed clinicians only; not a substitute for clinical judgement, diagnosis or local protocols.