Syncope Flashcards
Define: Syncope
Sudden, transient, complete loss of consciousness & postural tone w/ spontaneous recovery
What are some characteristics of syncope?
- Self-limited, rapid onset
- Variable warning symptoms
- Spontaneous, complete, & prompt recovery w/out meds/surgical intervention
What is syncope attributed to?
Cerebral hypoperfusion
What are “pre-syncopal” sx?
- Lightheadedness/dizziness
- Tunnel vision
- “Graying-out”
- Altered consciousness
- Palpitations
- Weakness
- Tremulousness
What are the causes of true syncope?
- Neurally-mediated
- Orthostatic
- Arrhythmia (brady, tachy)
- Cardiopulmonary
- *Unexplained in 1/3
What is #1 on your DDx?
Somatization disorder (psychogenic pseudo-syncope)
What sx are consistent w/ vasovagal syncope?
- Lightheaded
- Facial pallor
- Diaphoresis
- Nausea
What is the tilt table?
A provocative test for vasovagal syncope
What does the tilt table measure?
- Vasodepressor response
- Pauses
Describe how the tilt table is performed. What is it helpful for?
Pt tilted upright by 60-90 degrees
*Teaches pts how to recognize prodromal sx
Tilt table: What are normal vs abnormal findings?
- Normal: minimal drop in BP & increase in HR
- Abnormal: exaggerated drop in BP w/ or w/out drop in HR (associated w/ dizziness & lightheadedness)
When is a tilt table test indicated?
After recurrent episodes of unexplained syncope
What is the most common type of syncope?
Vasovagal syncope
What triggers vasovagal syncope?
- Heat
- Standing
- Exertion
Define: Orthostatic BP
≥ 20 drop in SBP or ≥ 10 drop in DBP (measured 3 minutes after supine to standing)
Which type of syncope has a higher risk of recurrent syncope?
Cardiac!
Which type of syncope has lower survival rates?
Cardiac!
Define: Sinus node dysfunction (type of bradyarrhythmia)
Intermittent pauses w/ alternating bradycardia & tachycardia (tachy-brady syndrome)
Define: AV block (type of bradyarrhythmia)
- 2nd degree, type II (Mobitz II)
- Complete heart block
What are types of tachyarrhythmias?
- SVT
- WPW
- AF/flutter w/ RVR
- Ventricular tachycardias
Psychogenic causes of syncope
- Not true syncope!
- Conversion disorder
- Pseudo syncope
- Pseudo-seizures
The San Francisco Syncope Rule identifies…
Low-risk pts for short-term serious outcomes who are unlikely to benefit from hospital admission
- Uses “CHESS” Criteria
What is the “CHESS” Criteria?
- CHF hx
- Hematocrit > 30%
- ECG abnormal
- SOB
- Systolic BP < 90
- If any of the above –> higher risk (consider hospital admission)
What is the goal of the Canadian Syncope Arrhythmia Risk Score?
Identify small subset of pts who suffer arrhythmia or death within 30 days of ED visit for syncope
Canadian Syncope Arrhythmia Risk Score: What are the 8 criteria scored?
- Vasovagal predisposition
- Hx of HD
- Any ED systolic BP <90 or > 180
- Troponin elevated
- QRS duration > 130
- Corrected QT interval >480
- ED dx of vasovagal syncope or cardiac syncope
What is the risk of arrhythmia in pts w/ a score of ≤ 0?
< 1%
What is the risk of arrhythmia in pts w/ a score of 1-3?
1.9-7.5%
What is the risk of arrhythmia in pts w/ a score of 4-8?
14.3-22.2%
In a young pt, what red flags might indicate he/she has VVS?
- Family hx of sudden death or early cardiac disease
- EKG abnormalities
- Exertional syncope
If the syncope has a long duration, what etiology might you think of?
Seizure!
Does a normal ECG rule out an arrhythmia cause?
No no no no no!
*May need to monitor on telemetry or wear an event monitor
Who should be admitted as inpatient?
Serious underlying conditions
Who should be admitted for observation?
“Intermediate-risk” pts
Who should be admitted for outpatient management?
Reflex-mediated syncope
*Prompt f/u necessary
What are life-threatening causes of syncope?
- Cardiac
- Acute severe hemorrhage
- Pulmonary embolism
- Subarachnoid hemorrhage
- Stroke, seizure, head injury
What is considered a “dx of exclusion”?
Orthostatic hypotension
What meds can cause syncope?
- Vasodilatory
- Cardiotoxic
- QT prolonging
What diagnostic tests should you perform for syncope?
- CBC, CMP, troponin
- ECG (holter/event monitor)
- Echo
If there is a cardiovascular abnormality, what additional dx tests should you perform?
- External loop recorder (2-6 wks)
- External patch (2-14 days)
- Outpatient telemetry (30 days)
- ICG
- EP study
- Carotid u/s
- Stress testing
- Chest imaging
- Neuro tests (MRI, EEG to r/o seizure)
- Tilt table
