From the Guidelines
When a patient presents with syncope, the initial workup should include a thorough history, physical examination, orthostatic vital signs, and an electrocardiogram (ECG) to identify the underlying cause, as recommended by the 2017 ACC/AHA/HRS guideline for the evaluation and management of patients with syncope 1. The workup for syncope should focus on identifying the cause by asking about prodromal symptoms, position when fainting, associated chest pain or palpitations, and medication use. Key elements of the initial evaluation include:
- A thorough history to identify potential causes such as cardiac, neurological, or vasovagal mechanisms
- Physical examination to assess for signs of cardiac or neurological disease
- Orthostatic vital signs to evaluate for orthostatic hypotension
- ECG to evaluate for arrhythmias, conduction abnormalities, or signs of structural heart disease Order basic laboratory tests including complete blood count, electrolytes, glucose, and cardiac enzymes if cardiac causes are suspected. For recurrent or concerning episodes, consider additional testing such as:
- Echocardiogram to evaluate for structural heart disease
- Holter monitoring for 24-48 hours to evaluate for arrhythmias
- Tilt-table testing for vasovagal syncope Brain imaging (CT or MRI) is warranted only if neurological symptoms are present, as recommended by the European Heart Journal guidelines on management of syncope 1. Carotid ultrasound may be appropriate for patients with risk factors for cerebrovascular disease. This comprehensive approach is necessary because syncope can result from various causes, and identifying the underlying cause is crucial for appropriate treatment and prevention of future episodes. It is essential to note that the initial evaluation should be guided by the patient's presentation and medical history, and additional testing should be tailored to the suspected cause of syncope. By following this approach, clinicians can provide effective care and improve outcomes for patients with syncope.
From the Research
Diagnostic Approach
The workup for syncope (fainting) involves a thorough evaluation to determine the underlying cause. The primary steps include:
- A careful history to identify potential causes and risk factors 2, 3, 4
- Physical examination, including orthostatic blood pressure measurements 2, 5
- Electrocardiographic (ECG) results to identify potential cardiac causes 2, 3, 4
Classification and Risk Stratification
Syncope can be classified into three primary categories:
- Cardiac syncope
- Reflex (neurogenic) syncope
- Orthostatic syncope Risk stratification is crucial to determine the need for hospital admission and further testing. Tools such as the Canadian Syncope Risk Score can be beneficial in this decision 2
Additional Testing
Additional testing may be considered if the initial findings are inconclusive and indicate possible adverse outcomes. This may include:
- Prolonged electrocardiographic monitoring 2, 4
- Stress testing 2
- Echocardiography 2
- Neuroimaging (only if a neurologic event or head injury is suspected) 2, 6
- Laboratory tests (based on history and physical examination findings) 2
Management
Management strategies involve pharmacologic and nonpharmacologic interventions, and cardiac pacing 6. Syncope units have been shown to improve the rate of diagnosis while reducing cost and are highly recommended 5