San Francisco Syncope Rule

The San Francisco Syncope rule identifies patients who cannot be considered low risk of adverse outcomes after a syncopal event.

Criteria include:

• History of congestive heart failure
• Hematocrit <30%
• Abnormal EKG (New ECG change from any source, any non-sinus rhythm on EKG or monitoring)
• Symptoms of shortness of breath
• Systolic BP <90 mmHg at triage

If any of these criteria are noted, patient cannot be considered "low risk" of a serious outcome. In this study, a serious outcome is defined as "death, myocardial infarction, arrhythmia, pulmonary embolism, stroke, subarachnoid hemorrhage, significant hemorrhage, or any condition causing a return ED visit and hospitalization for a related event."

While the original paper identified a 96% sensitivity and 62% specificity for serious outcome (with negative predictive value 99.2% and positive predictive value 24.8%), validation studies have reported inconsistent results.