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Symptoms > Syncope > Flashcards

Flashcards in Syncope Deck (12)
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1
Q

What is Syncope?

A

Transient loss of consciousness due to hypoperfusion of the brain (regardless of the cause)

“like dying, but you wake up”

2
Q

What is the direct effect of vagal nerve stimulation on the CV system?

A
  • Decreased HR
  • No effect on force of contraction of LV
  • No effect on PVR
3
Q

The (SNS/PNS) directly innervates the heart itself, the (SNS/PNS) does not.

A

SNS

PNS

4
Q

How do you treat vasovagal syncope?

A
  • Increase volume status (also mineralocorticoid drugs)
  • alpha 1 agonist: midodrine
  • Fludrocortisone not as effective
  • Possible beta blocker (strange)
    • Block triggering event (intense sympathetic discharge) to prevent event from occuring
  • Pacemaker
5
Q

What are some ways to diagnose vasovagal syncope?

A
  • ECG
  • Echocardiogram
  • Tilt-table test
  • Holter monitor
  • Implantable loop recorder
6
Q

young atheletes

LVH

outflow tract obstruction

A

hypertrophic cardiomyopathy

7
Q

How is HCM diagnosed?

A
  • Classic murmur
    • Harsh systolic murmur at apex & lower LSB
    • Increases from squatting to standing
    • Passive leg elevation decreases murmur
  • Echocardiogram
    • LV wall thickening
    • Septal hypertrophy
8
Q

What are the 4 phases of the ventricular myocyte AP?

A
  • Phase 0 - INa
  • Phase 1 - ITO
  • Phase 2 (Plateau Phase)
    • ICa-L, INaCa, IKr, IKs
  • Phase 3 (Repolarization Phase)
    • IKr, IKsIK1, IK-ACh/ATP
  • Phase 4 (Resting State)
    • IK1, IK-ACh/ATP
    • If (funny current, SA node, pacemaker)
9
Q

How does prolonged QT lead to TdP?

A
  • Prolonged QT leading to early after depolarization
  • Early after depolarization breaking threshold & leading to ectopic beat (TdP)
  • Sustained trigger activity
10
Q

In long QT what happens to each of these?

  • IKs
  • IKr
  • IK1
  • INa
  • ICa-L
A
  • IKs decrease
  • IKr decrease
  • IK1 decrease
  • INa increase
  • ICa-L increase
11
Q

________ prolongs the QT interval, but is rarely associated with TdP.

A

Amiodarone

12
Q

What medications cause acquired long QT?

A
  • Anti-arrhythmics
    • Class 1: Quinidine, Procainamide
    • Class 3: sotalol, amiodarone, dofetilide
  • Anti-depressants
  • Anti-psychotics
  • Antibiotics/Antifungals