What is the differential diagnosis and treatment approach for vertigo versus syncope?

Differential Diagnosis and Treatment Approach for Vertigo versus Syncope

Vertigo and syncope represent distinct clinical entities with different underlying pathophysiologies, requiring specific diagnostic approaches and management strategies.

Key Distinctions Between Vertigo and Syncope

Vertigo

• Definition: Illusion of movement (typically spinning) due to vestibular system dysfunction
• Consciousness: Patient remains conscious (no true loss of consciousness)
• Duration: Episodes can last seconds to days depending on cause
• Triggers: Often positional changes, head movements
• Associated symptoms: Nausea, vomiting, hearing changes, tinnitus

Syncope

• Definition: Transient loss of consciousness due to global cerebral hypoperfusion
• Consciousness: Complete but temporary loss of consciousness
• Duration: Brief (typically 6-8 seconds of unconsciousness)
• Triggers: Standing, emotional stress, situational factors, cardiac issues
• Associated symptoms: Prodromal lightheadedness, pallor, diaphoresis, complete recovery

Differential Diagnosis by Timing and Triggers

Vertigo Classification 1

1. Triggered episodic vestibular syndrome:

   • Benign Paroxysmal Positional Vertigo (BPPV) - most common
   • Superior canal dehiscence syndrome
   • Perilymph fistula

2. Acute vestibular syndrome:

   • Vestibular neuritis
   • Labyrinthitis
   • Posterior circulation stroke
   • Demyelinating diseases

3. Spontaneous episodic vestibular syndrome:

   • Vestibular migraine
   • Ménière's disease
   • Posterior circulation TIA

4. Chronic vestibular syndrome:

   • Anxiety/panic disorder
   • Medication side effects
   • Posttraumatic vertigo

Syncope Classification 1, 2

1. Reflex (neurally mediated) syncope:

   • Vasovagal syncope
   • Situational syncope (cough, micturition, post-exercise)
   • Carotid sinus syncope

2. Orthostatic hypotension:

   • Primary or secondary autonomic failure
   • Drug-induced
   • Volume depletion

3. Cardiac syncope:

   • Arrhythmias
   • Structural heart disease
   • Cardiovascular conditions (pulmonary embolism, aortic dissection)

Diagnostic Approach

For Suspected Vertigo

1. History focus:

   • Timing (acute, episodic, chronic)
   • Triggers (positional changes, specific movements)
   • Associated symptoms (hearing loss, tinnitus)

2. Key physical examination:

   • Dix-Hallpike maneuver for BPPV
   • Head impulse test
   • Assessment for nystagmus (direction, pattern)
   • HINTS examination (Head-Impulse, Nystagmus, Test of Skew) to distinguish peripheral from central causes

3. Additional testing when indicated:

   • Audiometry for suspected Ménière's disease
   • Neuroimaging for suspected central causes

For Suspected Syncope

1. History focus:

   • Circumstances prior to attack (position, activity)
   • Prodromal symptoms
   • Duration of unconsciousness
   • Recovery pattern

2. Key physical examination:

   • Orthostatic blood pressure measurements
   • Cardiac examination
   • Carotid sinus massage (when appropriate)

3. Initial testing:

   • 12-lead ECG
   • Basic laboratory tests (if volume depletion suspected)
   • Further cardiac evaluation for suspected cardiac syncope

Treatment Approach

Vertigo Management

1. BPPV:

   • Canalith repositioning procedures (Epley maneuver)
   • Vestibular rehabilitation

2. Vestibular neuritis/labyrinthitis:

   • Vestibular suppressants (meclizine 25-100 mg daily in divided doses) 3
   • Vestibular rehabilitation

3. Ménière's disease:

   • Salt restriction
   • Diuretics
   • Symptomatic treatment during attacks

4. Central causes:

   • Treatment of underlying condition
   • Urgent management for stroke

Syncope Management

1. Reflex syncope:

   • Patient education
   • Physical counterpressure maneuvers
   • Increased salt/fluid intake
   • Medication in refractory cases

2. Orthostatic hypotension:

   • Volume expansion
   • Compression stockings
   • Medication adjustment
   • Pharmacologic therapy when necessary

3. Cardiac syncope:

   • Treatment of underlying arrhythmia or structural heart disease
   • Device therapy when indicated

Common Pitfalls and Caveats

1. Misdiagnosis: Vertigo is often misdiagnosed as syncope and vice versa. Careful attention to whether true loss of consciousness occurred is critical 1, 4.

2. Overlooking dangerous causes: Central vertigo and cardiac syncope require urgent evaluation and treatment.

3. Elderly patients: Vertigo and syncope may coexist or have multiple contributing factors in older adults 4.

4. Rare presentations: Occasionally, neurally mediated syncope can present with positional vertigo-like symptoms 5.

5. Medication effects: Both conditions can be caused or exacerbated by medications.

By systematically evaluating the timing, triggers, and associated symptoms, clinicians can effectively differentiate between vertigo and syncope, leading to appropriate management strategies that address the underlying cause.