Syncope Flashcards
Differential Dx for syncope
- Vasovagal or reflex
- Orthostatic hypotension- dehydration, medication induced, aging
- Carotid sinus hypersensitivity (tight collar, turning had)
- Thoracic Outlet Syndrome (compression of arterial vessel by cervical rib)
- Cardiac arrhythmias
- Structural heart disease- MI, cardiomyopathy, valvular disease, amyloidosis
- Hypoglycemia
- Seizures or Epilepsy or Narcolepsy (sleep disturbances)
- Autonomic dysfunction (amyloidosis, diabetes, Parkinson’s disease) or POTS
- Psychogenic or illicit drug use
- Unexplained
- TIA or acute cerebrovascular event is very rare
Younger patients <35 with syncope
-More likely reflex syncope or POTS
-Dysrhythmias, exertional symptoms, and family history of sudden death (may indicate a more serious etiology)
12-lead electrocardiogram should be checked for abnormalities (eg, Brugada syndrome, prolonged QT)
Older patient with syncope
Syncope is most commonly associated with structural or ischemic heart disease, orthostasis, medications, or dehydration
Initial eval of syncope
- Electrolyte panel
- CBC with differential
- Fasting serum glucose
- TSH
- Electrocardiogram (ECG) (For everyone!)
- Chest x-ray (PA and LAT)
- Orthostatic vitals (blood pressure and heart rate)
- Other imaging as needed for injuries sustained during the event – CT head or other tests if injuries
Red flags on 12 lead
-Arrhythmia
-Conduction system disease
-ST-T wave changes consistent with ischemia or infarction
-Left ventricular hypertrophy
Prolonged interval (QRs, QTc); especially > 500 ms
-Severe bradycardia
-Pre-excitation (WPW- Wolf Parkinson White Syndrome)
Neurally mediated syncope
(Reflex, Neurocardiogenic, Vasovagal, Vasodepressor, or uncomplicated faint)-
- Vasovagal episodes due to non-specific triggers
- –Pain or emotional stress
- Situational or trigger syncope due to physical functions
- –Laughing, swallowing, coughing
- Typically younger patients (< 35) with negative family history
- Normal ECG
Postural Orthostatic Tachycardia Syndrome (POTS)
should be suspected when orthostatic symptoms are associated with a standing heart rate increase of ≥30 beats per minute for adults or ≥40 beats per minute in children and adolescents, in the absence of orthostatic hypotension
Orthostatic hypotension: autonomic dysfunction
Autonomic failure should be suspected when there is reproducible hypotension in the standing position without compensatory tachycardia, especially in a patient with underlying peripheral neuropathy, parkinsonism, or cerebellar ataxia.
Cardiogenic syncope
- Based on hx which may include sudden loss of consciousness, absence of a prodrome, or exertional symptoms.
- Consider cardiogenic syncope if any of the following are present: cardiac implanted device (eg, pacemaker), family history of sudden cardiac death, abnormal ECG or known arrhythmia, structural disease, or ischemic disease (including valvular heart disease, prolonged QT syndrome, hypertrophic cardiomyopathy, or Brugada syndrome).
Further eval
- Age >35 years
- Cardiac implantable device (PM, ICD)
- Family history of sudden death
- Abnormal ECG, known arrhythmia, structural or ischemic heart disease
- Suspected pulmonary embolism
- –When etiology is unclear, consult or curbside Cardiology/Electrophysiology or Neurology or appropriate specialty
Further eval w/ patients >35 years
- with a negative family history and normal ECG results may be considered for additional cardiac testing, including:
- -Echocardiography
- -Stress testing
- -Holter monitor / Event monitor
- –Tilt table testing may be considered for suspected reflex syncope in patients unresponsive to conservative treatment measures.
When to reassure
- No additional cardiac testing is typically recommended for patients age <35 years with…
- -negative family history
- -normal physical examination
- -normal ECG
- –AND no other associated conditions
- -Specific testing can be ordered based on differential diagnoses
