From the Guidelines
For patients with syncope, I recommend a comprehensive approach including non-pharmacological measures such as physical counterpressure maneuvers, increased fluid intake, and compression stockings, as these have been shown to be effective in reducing syncope recurrence, as demonstrated in a multicentre prospective trial 1.
Treatment Plan
The treatment plan should begin with non-pharmacological measures, including:
- Physical counterpressure maneuvers, such as leg crossing or hand grip, which have been shown to increase blood pressure and prevent syncope in patients with reflex syncope 1
- Increased fluid intake (2-3 liters daily) to help maintain blood volume
- Increased salt consumption (8-10g daily) to help maintain blood pressure
- Compression stockings (30-40 mmHg) to help improve blood flow and reduce orthostatic hypotension
Medication Management
For medication management, consider:
- Midodrine (2.5-10mg three times daily, with last dose before 6pm) to increase peripheral vascular resistance, although its use should be cautious in older males due to potential adverse effects on urinary outflow 1
- Fludrocortisone is not recommended as it has been shown to be ineffective in a small, randomized double-blind trial in children and there is no trial evidence to support its use in adults with reflex syncope 1
Autonomic Testing
Autonomic testing, including QSART (Quantitative Sudomotor Axon Reflex Test), can help evaluate autonomic function and distinguish between postganglionic sudomotor dysfunction and preganglionic lesions, guiding treatment decisions.
Follow-up and Education
Regular follow-up every 3-6 months is essential to monitor treatment efficacy and adjust medications as needed. Patients should be educated about symptom recognition and advised to keep a diary of syncope episodes to help identify triggers and evaluate treatment effectiveness.
Recent Guidelines
Recent guidelines from 2019 suggest that physical counterpressure maneuvers, such as leg crossing or hand grip, can be beneficial in preventing syncope in patients with vasovagal or orthostatic syncope 1. Additionally, the 2021 ACR Appropriateness Criteria for syncope recommend a comprehensive approach to diagnosis and management, including a detailed history and physical examination, and selective use of diagnostic tests 1.
From the Research
Treatment Plan for Syncope
The treatment plan for syncope involves a combination of lifestyle modifications, pharmacological interventions, and further testing to determine the underlying cause.
- Autonomic function testing is a safe and important diagnostic test for patients with syncope, helping to diagnose conditions such as orthostatic hypotension, delayed orthostatic hypotension, postural tachycardia syndrome, and neutrally mediated syncope 2.
- The 2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope emphasizes the importance of anamnestic criteria and ECG criteria of arrhythmic syncope, and revises the diagnostic value of provocative tests 3.
- For patients with vasovagal syncope, lifestyle modifications such as drinking 2 to 3 liters of fluids per day, consuming 10 grams of NaCl per day, and practicing counter-pressure maneuvers are recommended, and pharmacological interventions such as midodrine and fludrocortisone may be considered 4.
Autonomic Testing
Autonomic testing, including Quantitative Sudomotor Axon Reflex Testing (QSART), can help to assess the autonomic nervous system and guide treatment decisions.
- Autonomic function testing can help to diagnose several conditions, including orthostatic hypotension, delayed orthostatic hypotension, postural tachycardia syndrome, and neutrally mediated syncope 2.
- Cardiovascular autonomic tests, including Valsalva maneuver, active standing, carotid sinus massage, and tilt-testing, can reveal the etiology of syncope and/or orthostatic intolerance in paced patients 5.
Quantitative Sudomotor Axon Reflex Testing (QSART)
QSART is a test used to assess the function of the sudomotor axons, which are responsible for regulating sweat production.