Syncope

Jeffrey Chen7/6/09

Syncope

• Definition: Abrupt loss of consciousness and postural tone that reverses without intervention.

Differential Diagnosis

• Cardiac• Non-Cardiac– Neurological– Systemic/Metabolic– Psychiatric– Other

• Neurocardiac (Vasovagal)

Cardiac• Structural Abnormalities

• Cardiomyopathy (hypertrophic, restrictive, dilated)• Aortic Stenosis• Myocarditis• Pulmonary Hypertension• Postop Congenital heart disease (ex. Fontan)• Congenital coronary abnormality

• Electrical Disorders• Long QT syndrome• WPW syndrome• AV block• Ventricular tachycardia• Ventricular Fibrillation

Non Cardiac

• Neurologic– Seizures– Migraine Headaches – Transient Ischemic Attacks– Acute Vestibular Syndrome

Non Cardiac

• Systemic/Metobolic– Hypoglycemia– Electrolyte Abnormalities– Drugs/Toxins– Carbon Monoxide– Endocrinopathies

Non-Cardiac

• Psychiatric– Panic Attacks/Hyperventilation– Conversion Reaction– Depression

Non-Cardiac

• Other– Situational syncope• Cough• Micturation• Defecation• Neck stretching• Hair grooming

– Breath Holding Spells

Neurocardiac (Vasovagal)• Most Common variety of syncope• 25% precipitated by acute illness and anemia or by

noxious stimuli (fear, pain, exhaustion)• Prodromal symptoms– nausea/vomiting– Lightheadedness/vertigo– Visual disturbances– Sweating– SOB

• Mental alertness following the episode helpful in distinguishing from seizure

Neurocardiac (vasovagal) cont.

• Caused by:1. venous pooling which2. leads to vigorous contractions of an underfilled

ventricle3. This stimulates ventricular mechanoreceptors

which produces a paradoxic withdrawal of sympathetic activity

4. leading to hypotension, bradycardia or both

Management

• Goal is to increase circulating volume– Increased fluid intake– Mention potential diuretic effect of caffeine– Use more salt or salt tablets– Elastic Stockings

• Stress importance of “paying attention” to the warning signs– Avoid Noxious stimuli– Lying down before losing consciousness

Management

• Medications– Mineralocorticoids (hydroflurocortisone)– Beta-blockers– Alpha-agonists– Serotonin agonists