What are the treatment options for sincope?

Treatment Options for Syncope

The treatment of syncope must be directed at the underlying cause, with cardiac arrhythmias requiring appropriate treatment specific to the type of arrhythmia identified. 1

Classification and Treatment Approach

1. Cardiac (Arrhythmic) Syncope

Bradyarrhythmias

• Sinus node disease:
  • Cardiac pacing is indicated when syncope is demonstrated to be due to sinus arrest (with symptom-ECG correlation) 1
  • Pacing is indicated in patients with abnormal corrected sinus node recovery time 1
  • Eliminate drugs that may exacerbate bradycardia 1

Atrioventricular Block

• Cardiac pacing is the treatment of choice for:
  • Second-degree Mobitz II AV block
  • Advanced or complete AV block
  • Bundle branch block with positive electrophysiological study 1
  • Consider biventricular pacing in patients with depressed left ventricular ejection fraction and heart failure 1

Tachyarrhythmias

• Supraventricular tachycardias:

  • Catheter ablation is first-line treatment for AV nodal reciprocating tachycardia, AV reciprocating tachycardia, or typical atrial flutter 1
  • Antiarrhythmic drugs may be used as bridge to ablation or when ablation fails 1

• Ventricular tachycardias:

  • Implantable cardioverter defibrillator (ICD) is indicated for:
    • Documented ventricular tachycardia with structural heart disease 1
    • Sustained monomorphic VT induced at electrophysiological study in patients with previous myocardial infarction 1
    • Consider ICD for patients with inherited cardiomyopathies or channelopathies 1

• Torsades de pointes:

  • Immediate discontinuation of QT-prolonging drugs 1

2. Structural Cardiac or Cardiovascular Disease

• Treatment goals: Prevent symptom recurrence, reduce mortality risk, and treat underlying disease 1
• Approach:
  • Surgical treatment for severe aortic stenosis or atrial myxoma 1
  • Pharmacological therapy and/or revascularization for syncope associated with myocardial ischemia 1
  • For hypertrophic cardiomyopathy, specific arrhythmia treatment and ICD implantation to prevent sudden cardiac death 1
  • Treatment of acute cardiovascular conditions (pulmonary embolism, myocardial infarction, pericardial tamponade) should target the underlying process 1

3. Neurally-Mediated (Reflex) Syncope

• Vasovagal syncope:

  • Patient education and reassurance about benign prognosis 1
  • Avoidance of trigger events and situations 1
  • Physical countermeasures: leg crossing, squatting, isometric exercises 1
  • Volume expansion: increased salt intake, fluid intake (2-2.5L/day) 1
  • Consider fludrocortisone (0.1-0.2mg daily) for chronic volume expansion 1
  • Tilt training may be beneficial 1
  • Note: Evidence fails to support beta-blockers; they may worsen bradycardia in cardioinhibitory cases 1
  • Cardiac pacing may be considered in patients with cardioinhibitory vasovagal syncope with >5 attacks per year or severe physical injury and age >40 1

• Carotid sinus syndrome:

  • Cardiac pacing for cardioinhibitory or mixed carotid sinus syndrome 1

• Situational syncope:

  • Address trigger factors directly (e.g., suppressing cough in cough syncope) 1
  • Maintain central volume and use protected posture (sitting rather than standing) 1

4. Orthostatic Hypotension

• Drug-induced:

  • Eliminate or modify hypotensive medications 1
  • Discontinue diuretics and vasodilators when possible 1
  • Avoid alcohol 1

• Management strategies:

  1. Chronic expansion of intravascular volume (salt intake, fluid intake) 1
  2. Raise head of bed on blocks for gravitational exposure during sleep 1
  3. Use abdominal binders, compression stockings 1
  4. Small, frequent meals with reduced carbohydrate content 1
  5. Exercise of leg and abdominal muscles 1
  6. Consider midodrine (vasopressor) in refractory cases 2

Special Considerations

Device-Related Syncope

• Replace pulse generator or leads in case of battery depletion or failure 1
• Reprogram or replace pacemaker for pacemaker syndrome 1
• For ICDs with syncope despite appropriate therapy, consider device reprogramming, antiarrhythmic drugs, or catheter ablation 1

High-Risk Patients

• Patients with syncope in "high risk" settings (e.g., commercial vehicle drivers, pilots, machine operators) require special consideration for treatment 1
• In patients at high risk of sudden cardiac death, disease-specific treatment is warranted even if the exact mechanism of syncope remains uncertain 1

Common Pitfalls to Avoid

1. Misdiagnosis: Failure to distinguish true syncope from other causes of transient loss of consciousness (seizures, concussions, falls) 3
2. Inadequate evaluation: Rushing to multiple diagnostic tests without proper risk stratification 4
3. Overlooking cardiac causes: Arrhythmic syncope has poor prognosis if misdiagnosed, especially in patients with advanced heart disease 5
4. Treating symptoms without addressing cause: Focus on identifying and treating the underlying mechanism rather than just preventing falls 6
5. Inappropriate reassurance: While vasovagal syncope is generally benign from a mortality perspective, recurrent episodes can significantly impact quality of life and increase injury risk 7

By targeting the specific underlying cause of syncope, treatment can effectively reduce recurrence, prevent injury, and in some cases reduce mortality risk.