Arrhythmias

Question 1

What is the pacemaker of the heart?

Answer 1

SA node
autonomic nervous systems controls the SA node

Question 2

What are the lethal arrhythmias?

Answer 2

1. asystole (flatline)/cardiac standstill
2. ventricular tachycardia (V tach)
3. ventricular fibrilation

Question 3

What is asystole(flateline)/caridac standstill ?

Answer 3

no detectable electrical activity of the myocardium

lethal arrhythmia

Question 4

What is ventricular arrythmia?

Answer 4

• ventricules contract at a rapid rate autonomously
• no time for diastole
• cardiac output can drop to zero
• major cause for sudden cardiac death

lethal arrythmia

Question 5

What is ventricular fibrilation?

Answer 5

• contractions are completley uncoordinated
• almost non-existent cardiac output
• leads to death
• “bag of worms”

Question 6

What is the mechanism of Long QT syndrome?

Answer 6

• some heart cells are taking a long time to repolarize - so they aren’t synched up well which can lead to tachycardia known as Torsade De Pointes
• caused by abnormal ion channels

Question 7

Long QT indicates a deficit in ?

Answer 7

ventricular repolarization

Question 8

Classic genetic Long QT Syndrome is known as…

Answer 8

Romano-Ward Syndrome

not truly a syndrome though b/c only heart affected

Question 9

What is the inheritance pattern for LQTS?

Answer 9

AD

Question 10

What are presenting features of LQTS?

Answer 10

• syncope
• seizures
• sudden cardiac death

can also be triggered by things like exercise, anxiety, jumping in a pool….

Question 11

3 main genes for LQTS/Romano-Ward Syndrome

Answer 11

• KCNH2
• KCNQ1
• SCN5A

on channel genes

Question 12

Homozygosity or compound heterozygosity in KCNQ1 and KCNE2 leads to…

Answer 12

Jervell and Lange-Nielsen Syndrome
* LQTS
* sensorineural hearing loss

truly a syndrome b/c 2 systems affected

Question 13

What is a genetic counseling factor to keep in mind if someone is diagnosed with Jervell and Lange-Nielsen Syndrome?

Answer 13

New mutation rate is low, so parents should be chekd for LQTS

Question 14

Andersen Syndrome is a LQTS syndrome caused by heterozygous variants in KCNJ2. What is one of the characteristic features in these patients?

Answer 14

• hypokalemic periodic paralysis
• low potassium while limp - can go on for hours -> days (not lethal)

Question 15

Timothy Syndrome is characterized by ?. It is caused by heterozygous variants in CACNA1C. It is associated with lots of oher issues including HCM, joint hypermobiliy, and autism.

Answer 15

LQTS

Question 16

TTN = elasticity and contraction, cardiomyopathies and muscular dystrophies
TTR = transthyretin, associated with amyloidosis and neves and heart

Question 17

In Brugada syndrome there is an elevation of the…

Answer 17

ST segment

on EKG

Question 18

Brugada Syndrome gene

Answer 18

SCN5A

Question 19

Brugada Syndrome is a(n) ? disorder and can cause ?

Answer 19

Brugada Syndrome is an arrhythmia disorder and can cause sudden death in a healthy, young person

Question 20

Wolff-Parkinson-White Syndrome is characterized by 2 distinct EKG findings:
1. shortened PR interval
2. presence of a ? wave

Answer 20

delta

Question 21

Catecholaminergic Polymorphic Ventricular Tachycardia gene

Answer 21

RYR2

Question 22

Catecholenergic Polymorphic Ventricular Tachycardia
* age of onset
* distinguishing features
* presentation

Answer 22

• late childhood
• bidirectional or polymorphic venricular tachycardia during exercise and excitement
• cardiac arrest, syncope, sudden death

highly lethal arrhythmia

Question 23

Certain medications need to be avoided with LQTS. What indication do many of these meds fall under?

Answer 23

psych meds