SYNCOPE "FAINTING" CAUSES?

Fainting, "blacking out," or syncope is the temporary loss of consciousness followed by the return to full wakefulness. This loss of consciousness may be accompanied by loss of muscle tone that can result in falling or slumping over. To better understand why fainting can occur; it is helpful to explain why somebody is awake.

Causes of syncope

·         Neurally mediated syncope (NMS) - also called reflex syncope:

ü  Vasovagal syncope (common faint)

ü  Situational syncope - eg, cough, sneeze, gastrointestinal stimulation (swallowing, defecation, visceral pain), micturition.

ü  Carotid sinus hypersensitivity.

ü  Glossopharyngeal neuralgia.

·         Orthostatic hypotension (postural hypotension)

·         Autonomic failure - eg, multiple system atrophy, Parkinson's disease, diabetes, amyloidosis.

·         Medications - eg, antihypertensives.

·         Hypovolaemia - eg, haemorrhage, vomiting, diarrhoea, Addison's disease.

·         Post-exercise.

·         Postprandial.

·         Cardiac arrhythmias:

ü  Sick sinus syndrome, atrioventricular (AV) conduction system disease.

ü  Paroxysmal supraventricular tachycardia, ventricular tachycardia.

ü  Inherited syndromes - eg, long QT syndrome, Brugada's syndrome.

ü  Malfunction of pacemaker or implantable cardioverter defibrillator (ICD)

ü  Drug-induced arrhythmias.

·         Structural cardiac or cardiopulmonary disease:

ü  Obstructive cardiac valvular disease.

ü  Acute coronary syndrome.

ü  Hypertrophic obstructive cardiomyopathy.

ü  Atrial myxoma.

ü  Acute aortic dissection.

ü  Pericardial disease or tamponade.

ü  Pulmonary embolus or pulmonary hypertension.

·         Cerebrovascular:

ü             Vascular steal syndromes - eg, subclavian steal syndrome.

·         Substance abuse, alcohol intoxication.

·         Psychogenic: factitious, anxiety, panic attacks, hyperventilation.