Table 3:

Disposition

ACC/AHA/HRS		ESC	Important Similarities	Important Differences	Other Notes
•	Class I: Hospital evaluation and treatment recommended if patient has a potentially relevant serious medical condition	Class I: Low-risk: discharge from ED; high-risk: admission and evaluation; medium risk: observe in ED or syncope unit instead of admission	Both guidelines rely on risk stratification	ACC/AHA gives recommendations based on seriousness of underlying illness, while ESC focuses on presenting features	N/A
•	Class IIa: Manage presumptive reflex-mediated syncope in outpatient setting; in intermediate-risk patients with unclear etiology, structured ED observation can reduce hospital admission (structured = expedited access to cardiology/testing)
•	Class IIb: Manage selected patients with suspected cardiac syncope in outpatient setting

ACC: American College of Cardiology; AHA: American Heart Association; HRS: Heart Rhythm Society; ESC: European Society of Cardiology; ED: emergency department; N/A: not applicable.