Syncope, commonly known as fainting, is a temporary loss of consciousness and postural tone due to transient cerebral hypoperfusion. It’s a common clinical problem and can be caused by a variety of factors.
Causes of Syncope:
- Vasovagal Syncope: Triggered by prolonged standing, emotional stress, pain, or heat exposure.
- Orthostatic Hypotension: Sudden drop in blood pressure upon standing, due to dehydration, medications, or autonomic dysfunction.
- Cardiac Syncope: Arrhythmias (bradycardia or tachycardia), structural heart disease (aortic stenosis, hypertrophic cardiomyopathy), or ischemic heart disease.
- Neurological Causes: Transient ischemic attacks, vertebrobasilar insufficiency.
- Metabolic and Other Causes: Hypoglycemia, hyperventilation, anemia.
Diagnosis:
- History:
- Onset and Duration: Abruptness, duration of unconsciousness.
- Precipitating Factors: Position changes, stress, pain, eating, cough, exertion.
- Associated Symptoms: Palpitations, chest pain, shortness of breath, neurological symptoms, incontinence, seizures
- Past Medical History: Cardiovascular, neurological disorders, diabetes, medication use.
- Family History: Of syncope or sudden cardiac death.
- Physical Examination:
- Vital Signs: Blood pressure (in different positions), heart rate.
- Cardiovascular Exam: Heart murmurs, irregular heartbeats, signs of heart failure.
- Neurological Exam: Focal deficits, gait abnormalities.
- ENT Examination: To rule out vestibular causes.
- Investigations:
- Electrocardiogram (ECG): To detect arrhythmias or ischemic changes.
- Echocardiogram: If structural heart disease is suspected.
- Blood Tests: CBC, electrolytes, glucose, renal function.
- Tilt Table Test: If vasovagal or orthostatic syncope is suspected.
- Holter Monitoring or Event Recorder: For suspected arrhythmic causes.
- Neurological Investigations: CT/MRI of the head, carotid ultrasound, if a neurological cause is suspected.
Differential Diagnosis (DDx):
- Seizure Disorders
- Transient Ischemic Attack (TIA)
- Hypoglycemia
- Psychogenic Pseudosyncope
- Vertigo
Management:
- General Measures:
- Education and Avoidance of Triggers: For vasovagal syncope.
- Hydration and Salt Intake: To manage orthostatic hypotension.
- Review and Adjust Medications: That could contribute to syncope.
- Specific Treatment Based on Cause:
- Vasovagal Syncope: Patient education, physical counterpressure maneuvers.
- Orthostatic Hypotension: Fludrocortisone, midodrine, compression stockings.
- Cardiac Syncope: Pacemaker for bradycardia, anti-arrhythmic drugs, correction of structural abnormalities.
- Neurological Causes: Addressing the specific neurological condition.
- Lifestyle Modifications:
- Avoiding Dehydration and Alcohol
- Gradual Position Changes
- Adequate Nutrition
Follow-Up and Monitoring:
- Regular Follow-up: Especially if on medication or with cardiac/neurological causes.
- Monitoring for Recurrence: Patient education on recognizing prodromal symptoms.
- Driving Restrictions
Referral:
- Cardiologist or Electrophysiologist: For suspected cardiac syncope.
- Neurologist: If a neurological cause is suspected.
Managing syncope effectively requires a tailored approach based on the underlying cause, the patient’s overall health, and the risk of recurrence or serious outcomes.