Key Recommendations
1). Initial evaluation
- Conduct physical exam, history (with careful attention to factors in Tables 1 & 2) and resting electrocardiogram (ECG) to identify a possible cause (see Tables 2 & 3).
2). Disposition from the emergency department (ED)
- Hospital admission is recommended for patients with serious medical conditions that might be relevant to the identified cause of syncope.
- For admitted patients with syncope suspected to be of cardiac etiology, admit to a telemetry unit for continuous cardiac monitoring.
- Patients with presumptive reflex-mediated syncope (i.e., situational syncope) may be managed as outpatients if they do not have serious medical conditions.
- ED observation units are appropriate for patients at intermediate risk who have an unclear cause of syncope.
3). Testing
- Only if the initial clinical evaluation does not reveal an etiology, targeted blood tests may be reasonable (e.g., CBCD, CMP, cardiac enzymes).
- For selected patients with syncope suspected to be due to cardiovascular causes, certain tests may be useful, including the following:
- For structural heart disease: transthoracic echocardiography
- For cardiac etiology: cardiac computed tomography or magnetic resonance imaging
- For syncope during exertion: echocardiogram and exercise stress testing
- For arrhythmia: electrophysiologic studies
4) DMV Reporting
- All cases of syncope requiring hospitalization should be reported to the DMV as they constitute an example of a “lapse in consciousness.”
Table 1: Risk Factors for Syncope Requiring Hospitalization
Male sex
Older age (>60 y)
No prodrome
Palpitations preceding loss of consciousness
Exertional syncope
Cancer
Structural heart disease
Heart failure
Cerebrovascular disease
Family history of Sudden Cardiac Death
Diabetes mellitus
Trauma
Table 2: Physical Examination or Laboratory Investigation
Abnormal ECG (e.g., pathologic Q waves, non-sinus rhythm or AV block)
Evidence of bleeding
Persistent abnormal vital signs (especially SBP<90 and HR<50 or >140)
Elevated troponin I or troponin T
Table 3: Examples of Serious Medical Conditions That Might Warrant Consideration of Further Evaluation and Therapy in a Hospital Setting
Cardiac Arrhythmic Conditions
- Sustained or symptomatic Ventricular tachycardia
- Symptomatic conduction system disease or Mobitz II or third-degree heart block
- Symptomatic bradycardia or sinus pauses not related to neurally mediated syncope
- Symptomatic Supraventricular tachycardia
- Pacemaker/ICD malfunction
- Inheritable cardiovascular conditions predisposing to arrhythmias
Cardiac or Vascular Nonarrhythmic Conditions
- Cardiac ischemia
- Severe aortic stenosis
- Cardiac tamponade
- Hypertrophic cardiomyopathy
- Severe prosthetic valve dysfunction
- Pulmonary embolism
- Aortic dissection
- Acute Heart failure
- Moderate-to-severe Left Ventricular dysfunction
Noncardiac Conditions
- Severe anemia/gastrointestinal bleeding
- Major traumatic injury due to syncope
- Persistent vital sign abnormalities (especially SBP<90 and HR<50 or >140)
