From the Guidelines
The workup for a 21-year-old female with postural syncope should begin with a thorough history and physical examination, focusing on orthostatic vital signs, as recommended by the 2017 ACC/AHA/HRS guideline for the evaluation and management of patients with syncope 1. The initial evaluation should include a complete blood count, basic metabolic panel, and electrocardiogram to rule out anemia, electrolyte abnormalities, and cardiac arrhythmias. Key aspects to consider in the history and physical examination include:
- Orthostatic vital signs to confirm orthostatic hypotension (a drop in systolic blood pressure ≥20 mmHg or diastolic blood pressure ≥10 mmHg within 3 minutes of standing)
- Volume depletion
- Medication side effects
- Autonomic dysfunction Additional testing may be considered based on the initial findings, such as:
- Tilt-table test to reproduce symptoms
- 24-hour ambulatory blood pressure monitoring
- Echocardiogram if structural heart disease is suspected Management typically begins with non-pharmacological approaches, including:
- Increasing fluid intake (2-3 liters daily)
- Salt supplementation (aiming for 8-10g daily)
- Compression stockings
- Avoiding prolonged standing If these measures are insufficient, medications like fludrocortisone (starting at 0.1mg daily) or midodrine (2.5-10mg three times daily) may be considered, as they have been shown to be beneficial in patients with syncope due to neurogenic orthostatic hypotension 1. It is essential to use these medications cautiously, monitoring for supine hypertension, especially with midodrine, which should not be taken within 4 hours of bedtime. The European Heart Journal guidelines from 2009 also support the importance of a thorough initial evaluation, including history, physical examination, and electrocardiogram, to determine the etiology of syncope and assess the risk of cardiovascular events or death 1.
From the Research
Diagnostic Approach
The workup for a 21-year-old female with postural syncope typically involves a detailed history, physical examination, and some basic tests to determine the underlying cause of the syncope. The primary goal is to identify if the syncope is due to a cardiac, reflex (neurogenic), or orthostatic cause 2.
Initial Evaluation
The initial evaluation should include:
- A thorough medical history to identify any potential causes or contributing factors
- Physical examination, including orthostatic blood pressure measurements to assess for orthostatic hypotension
- Electrocardiography (ECG) to evaluate for any cardiac abnormalities
Further Testing
If the initial findings are inconclusive, further testing may be considered, such as:
- Prolonged electrocardiographic monitoring
- Stress testing
- Echocardiography, particularly if cardiac syncope is suspected 2
- Tilt-table testing for suspected reflex syncope or orthostatic hypotension 3
- Laboratory tests based on the patient's history and physical examination findings
Risk Stratification
Patients should be stratified into lower or higher risk of adverse outcomes based on their history, physical examination, and ECG results 2. This can inform decisions regarding hospital admission and the need for further evaluation. Risk stratification tools, such as the Canadian Syncope Risk Score, may be beneficial in this decision.
Management
Most patients with postural syncope can be managed in an outpatient setting, and hospital admission is rarely warranted 4. The management approach will depend on the underlying cause of the syncope and may involve simple measures to reduce recurrence, such as increasing fluid and salt intake, or medication in some cases 5.