041315 syncope

Question 1

mechanism of syncope

Answer 1

hypoperfusion to brain

Question 2

one thing most concerned about when presenting with syncope

Answer 2

arrhythmia

Question 3

3 types of syncope

Answer 3

reflex mediated (stress, situational, vasovagal)
orthostatic
cardiac

also seizure

Question 4

neurocardiogenic dysfxn

Answer 4

also known as vasovagal syncope

Question 5

what is the direct effect of vagal nerve stimulation of CV system?

Answer 5

decreases HR
no effect on force of contraction of LV
no effect on PVR (blood vessels aren’t directly innervated by the vagus nerve, but they do hv Ach receptors)

Question 6

mechanism of vasovagal syncope

Answer 6

decrease in HR

Question 7

how is autonomic outflow controlled

Answer 7

by NTS of medullasends signals to activate sympath or vagus nerve

Question 8

Bezold Jarisch reflex

Answer 8

venous pooling and sympathetic activation cause vigorous contrac of poorly filled ventricle. this activates C fibers which go to brainstem to activate vagal reflex, causing bradycardia and vasodilation.–leading to syncope

Question 9

diagnosing syncope-what tests can you do?

Answer 9

glucose
ECG (EVERYONE GETS THIS)
ECHO (not everyone gets)
tilt table test
Holter monitor
implantable loop recorder (can last years)
urinalysis (dehydrated?)
cardiac markers
hemoglobin (hemorrhage from GI or ectopic pregnancy?)

Question 10

tx for vasovagal syncope

Answer 10

fluids
SSRIs
beta blockers (not as effec)
alpha1 agonists

pacemaker (if severe)

Question 11

harsh ejection systolic murmur at apex and lower LSB that increases from squatting to standing and is decreased with passive leg elevation

Answer 11

hypertrophic cardiomyopathy

Question 12

with syncope, after getting EKG, what do you want to look for EKG?

Answer 12

QT interval (should be under 0.44 sec)
one bold box is 0.2 sec

arrhythmia

AV block (a fib, a flutter, v tach)

do you see a P, Q, T in succession?