From the Guidelines
The outpatient workup for syncope should begin with a thorough history and physical examination, focusing on the circumstances surrounding the event, prodromal symptoms, and any associated features, as recommended by the European Heart Journal guidelines 1. The initial evaluation should include orthostatic vital signs, a 12-lead ECG, and basic laboratory tests (complete blood count, basic metabolic panel, and cardiac enzymes if recent) to identify potential causes of syncope, such as orthostatic hypotension, cardiac arrhythmias, or metabolic disorders 1. The following key points should be considered in the outpatient workup for syncope:
- A thorough history and physical examination to identify potential causes of syncope
- Initial testing, including orthostatic vital signs, 12-lead ECG, and basic laboratory tests
- Further testing, such as echocardiogram, ambulatory cardiac monitoring, and exercise stress testing, based on the suspected cause of syncope
- Consideration of tilt-table testing for suspected vasovagal syncope and carotid sinus massage for patients over 40 with no carotid bruits
- Neurological evaluation, including EEG or brain imaging, only when seizure activity is suspected or with focal neurological findings This systematic approach helps identify the underlying cause of syncope, which is essential for appropriate management and prevention of recurrence, as emphasized by the American College of Cardiology Foundation 1.
From the Research
Outpatient Workup for Syncope
The outpatient workup for syncope involves a thorough evaluation to determine the underlying cause of the condition. The following steps are typically taken:
- History-taking: A detailed medical history is crucial in identifying the cause of syncope 2, 3.
- Physical examination: A comprehensive physical examination, including orthostatic blood pressure measurements, is essential in evaluating patients with syncope 4, 2, 5.
- Electrocardiogram (ECG): A 12-lead ECG is recommended for the initial evaluation of patients with suspected syncope 3.
- Risk stratification: Patients are designated as having lower or higher risk of adverse outcomes according to history, physical examination, and electrocardiographic results 4, 5.
- Additional testing: Prolonged electrocardiographic monitoring, stress testing, and echocardiography may be beneficial in patients at higher risk of adverse outcomes from cardiac syncope 4.
- Laboratory tests: Laboratory tests may be ordered based on history and physical examination findings, such as hemoglobin measurement if gastrointestinal bleeding is suspected 4.
- Tilt-table testing: Outpatient evaluation with tilt-table testing is appropriate for patients with suspected reflex syncope or orthostatic hypotension 5.
Classification of Syncope
Syncope can be classified into three primary categories:
- Cardiac syncope: Caused by cardiac conditions, such as arrhythmias or structural heart disease 4, 2, 3.
- Reflex syncope: Caused by reflex mechanisms, such as vasovagal syncope or situational syncope 2.
- Orthostatic syncope: Caused by orthostatic hypotension, which is a decrease in systolic blood pressure upon standing 2, 5.
Management of Syncope
The management of syncope depends on the underlying cause and risk stratification. Patients with life-threatening causes of syncope should be managed urgently and appropriately 2, 6. In patients with reflex or orthostatic syncope, addressing exacerbating medications and providing general measures to increase blood pressure is important 2. Specialist opinion and correction of the underlying problem are warranted in patients with cardiac syncope 2, 5.