What is the treatment for reflex syncope?

Treatment of Reflex Syncope

The cornerstone of reflex syncope treatment is education, lifestyle measures, and physical counterpressure maneuvers (PCMs), which have been proven to significantly reduce syncope recurrence and should be implemented as first-line therapy for all patients. 1

First-Line Management

Education and Lifestyle Modifications

• Provide reassurance about the benign nature of the condition
• Teach patients to recognize early prodromal symptoms
• Avoid triggers:
  • Hot crowded environments
  • Prolonged standing
  • Volume depletion
  • Alcohol consumption
  • Agents that lower blood pressure (α-blockers, diuretics)

Physical Counterpressure Maneuvers (PCMs)

• Isometric PCMs are highly effective and should be taught to all patients with prodromal symptoms
• Techniques include:
  • Leg crossing with muscle tensing
  • Hand grip and arm tensing
  • Squatting

These maneuvers have been shown to reduce yearly syncope burden by 39% compared to conventional therapy alone, with no adverse events reported 1.

Second-Line Management

For patients with frequent, unpredictable syncope that continues despite first-line measures, consider:

Volume Expansion

• Increased salt and fluid intake (targeting 2-3L of fluids daily and 10g of NaCl) 1
• Particularly important in patients without hypertension

Pharmacological Therapy

• Midodrine may be indicated in patients with vasovagal syncope refractory to lifestyle measures 1
  • Dosage: Start with 2.5mg in patients with renal impairment; typical dose 5-20mg three times daily 2
  • Caution: Monitor for supine hypertension; last daily dose should be taken 3-4 hours before bedtime 2
  • Contraindications: Avoid in patients with urinary retention, and use cautiously with cardiac glycosides 2

Tilt Training

• May be useful for education in highly motivated young patients with recurrent vasovagal symptoms triggered by orthostatic stress
• Limited by low patient compliance and lack of proven long-term efficacy 1

Third-Line Management

Cardiac Pacing

• Should be considered in specific situations:
  • Patients with dominant cardioinhibitory carotid sinus syndrome
  • Patients >40 years with frequent recurrent reflex syncope and documented spontaneous cardioinhibitory response during monitoring
  • Not indicated in the absence of a documented cardioinhibitory reflex 1

Important Considerations

1. β-Adrenergic blocking drugs are not indicated for reflex syncope treatment 1

2. Situational syncope (e.g., cough, micturition, defecation syncope):

   • Treatment relies on avoiding or ameliorating triggering events
   • Response may be attenuated by maintaining central volume and adopting protected posture 1

3. Carotid sinus syndrome:

   • Dual-chamber pacing is preferred when bradycardia is documented 1

Special Populations

For elderly patients with orthostatic hypotension contributing to syncope:

• Abdominal binders or compression stockings may help reduce gravitational venous pooling 1
• Sleeping with head of bed elevated (10°) can prevent nocturnal polyuria and maintain better fluid distribution 1

Treatment Algorithm

1. Start with education, trigger avoidance, and PCMs for all patients
2. If syncope persists, add increased salt/fluid intake
3. For refractory cases, consider midodrine (if no contraindications)
4. Consider cardiac pacing only for documented cardioinhibitory responses in appropriate patients

The goal of therapy is primarily prevention of recurrence and associated injuries, and improvement in quality of life, not prolongation of survival 1.