Syncope

Question 1

T/F: Syncope is defined by transient loss of consciousness due to irreversible disturbance of cerebral function with inability to maintain postural tone.

Answer 1

False. REVERSIBLE disturbance of cerebral function

Question 2

Acute cerebral ischemia from decrease blood flow occurs if: ____ OR ____

Answer 2

systolic bp less than 70

mean arterial pressure less than 30-40

Question 3

BP= (____) x resistance = (___ x HR) x (R)

Answer 3

cardiac output

stroke volume

Question 4

What type of syncope?

syncope from reflex mechanisms associated with inappropriate vasodilation, bradycardia, or both

Answer 4

Neutrally mediated syncope

Question 5

Which of the following is NOT a cause of decreased stroke volume?
A. Preload abnormalities
B. Afterload abnormalities
C. Decreased contractility

Answer 5

Gotcha! All of the are causes of decreased stroke volume.

Question 6

Direct pharmacological (nitrates), decreased blood volume, and valsalva and tussive syncope are causes of ____

Answer 6

Syncope secondary to decreased stroke volume due to PRELOAD ABNORMALITIES (assoc. w/ HYPOTENSION of orthostatic nature)

Question 7

Pulmonary HTN or stenosis, clot or myxoma obstructing mitral valve, aortic outflow tract obstruction, prosthetic valve clot are causes of ____

Answer 7

Syncope secondary to decreased stroke volume AFTERLOAD ABNORMALITIES (OBSTRUCTIONS – fixed or intermittent)

Question 8

Too few or no beats =

Answer 8

Bradydysrhythmias

Question 9

Too rapid heart rate =

Answer 9

tachydysrhythmias

Question 10

Carotid sinus syncope is characterized by marked (tachycardia/bardycardia) secondary to (increase/decrease) to SA or AV node function +/- marked (increase/decrease) in peripheral arterial resistance

Answer 10

bradycardia
decrease
decrease

(syncope neurally mediated)

Question 11

If symptoms occur while standing up (DECREASED bp and INCREASED HR on standing) then the causes may be (2) ____

Answer 11

1. PRELOAD abnormalities (decreased volume)

2. Abnormalities of arteriolar resistance (SECONDARY orthostatic hypotension)

Question 12

T/F: Primary orthostatic hypotension is charcterized by significant drop in BP and increase in heart rate when standing.

Answer 12

False. Minimal change in HR

Question 13

If symptoms primarily on exertion then the causes may be (2) ____

Answer 13

1. Fixed AFTERLOAD abnormalities (aortic stenosis)

2. Exercise induced dysrhythmias

Question 14

If symptoms anytime (esp. if sitting or recumbent) then the causes may be (2) _____

Answer 14

1. Dysrhythmias

2. Intermittent afterload abnormalities (intermittent obstruction of prosthetic heart valve)

Question 15

T/F: Cardiac massage should be performed if history suggestive of bruit.

Answer 15

False. Do NOT do a if bruit present. Perform if history suggestive of carotid sinus syncope

Question 16

What test to perform?

neurocardiogenic syncope suspected

Answer 16

Tilt table testing

Question 17

What test to perform?

afterload obstructions or myocardial dysfunction

Answer 17

Echocardiology

Question 18

What test to perform?

exercise induced dysrhythmias or to confirm angina suspicion

Answer 18

Treadmill exercise EKG

Question 19

What test to perform?

syncope is unexplained

Answer 19

Electrophysiologic consultation and catheterization

Question 20

What type of syncope?
Initiated by unpleasant circumstance (sight of blood) that initiates peripheral vasodilation, sweating and tachycardia followed by bradycardia and nausea.

Answer 20

Vasodepressor syncope (vasovagal)

Question 21

What type of syncope?
Stimulus causing hypotension triggers involving activation of intramyocardial baroreceptors that reflexly inhibit efferent sympathetic tone and increased efferent parasympathetic tone.

Answer 21

Neurocardiogenic syncope