syncope

Define

Def: transient loss of consciousness accompanied by loss of postural tone, followed by complete resolution without intervention.

Causes

[1] Cardiac related syncope:

Structural cardiac lesion → Limit heart's ability to ↑ cardiac output

• hypertrophic cardiomyopathy

• aortic stenosis

• pulmonary embolism

• MI

Dysrhythmia → sudden and without prodrome

• ventricular tachycardia

• Torsades des pointes

• supraventricular tachycardia

• bradycardia

• Brugada or QT syndrome → in young people

[2] Vasovagal syncope:

symp: dizziness, nausea, pallor, diaphoresis, \downarrow vision

sign: hypotension, bradycardia

hx: phlebotomy, prolong standing in warm place, fear

[3] Situational syncope:

autonomic reflex response from physical stimulus

• micturition, defecation, extreme coughing

  
  

4. Carotid Sinus Hypersensitivity

• Hx of shaving, head turning, wearing constricting collar

5. Orthostatic Syncope

• Sudden change in posture after recumbence is associated with inadequate compensatory increase in HR and peripheral vascular resistance

• Due to ↓ intravascular volume or poor vascular tone

• Causes:

  • Peripheral neuropathy

  • Spinal cord injury

  • Medication side effect

6. Neurologic Syncope

• Brainstem ischemia or vertebrobasilar insufficiency → diplopia, vertigo, focal neurological deficits, nausea

• Intermittent obstruction of brachiocephalic or subclavian artery → hx of upper extremity exercise

• Subarachnoid hemorrhage → headache, trauma

Dd

D.D - Seizures

Brief tonic-clonic movement

Postictal state

Tongue biting

Incontinence

Epileptic aura

Diagnosis

Diagnosis

• Sudden without warning → suggest dysrhythmias

• Preceding exertion → structural cardiopulmonary lesion

• Palpitation or chest pain → cardiac etiology

• Vertigo or focal weakness → neurologic cause

• Back or Abd. pain → leaking abdominal aortic aneurysm or ruptured ectopic pregnancy

• Orthostatic hypotension with SBP drop 20 mmHg upon standing → vasovagal syncope

• BP differential between upper extremities > 20 { mmHg} → subclavian steal syndrome

• ECG → ischemia or dysrhythmia

  • prolonged QT interval → torsades des pointes

  • PR interval shortening with delta wave → Wolff-Parkinson-White syndrome