Cardiology

Question 1

What do class 1 antiarrhythmics do?

Answer 1

Block Na channels
eg. Flecainide
Prolongs depolarisation - how long the ventricle takes to contract (Prolongs QRS)

Question 2

What do class 2 antiarrythmic agents do?

Answer 2

Beta blockers
Slow AV node conduction

Question 3

What do class 2 antiarrythmic agents do?

Answer 3

Potassium channel blockers
Eg. amiodarone, sotalol
Prolong QT

Question 4

What do class 4 antiarrythmic agents do?

Answer 4

Calcium channel blockers
Prolong AV node conduction
eg. Verapamil

Question 5

Side Effects of Flecainide?

Answer 5

Tingling and constipation
Proarrhythmic
QRS widening
Milk can decrease GI absorption

Question 6

Most serious side effect in Sotalol?

Answer 6

QTc prolongation
Bradycardia and lethargy

Question 7

Which anti arrhythmic is contraindicated in infants <1year?

Answer 7

Verapamil
Also contraindicated in WPW

Question 8

Which medications are contraindicated in WPW?

Answer 8

Verapamil
Digoxin

Question 9

What is multifocal atrial tachycardia?

Answer 9

When there are 3 or more different non sinus P wave morphologies?
Tx with Antiarrhythmics class 1 or 3

Question 10

What is the management of atrial flutter?

Answer 10

Synchronised DC cardioversion
If that doesn’t work Amiodarone or Sotalol
If giving flecainide MUST be given with beta blocker.

Question 11

What does orthodromic mean?

Answer 11

When the electrical activity goes down through the AV node and then back up through the accessory pathway (narrow QRS complex)

Question 12

What does antidromic mean?

Answer 12

When the electrical activity goes down through the accessory pathway and then back up through the AV node (broad QRS complex - looks like VT)

Question 13

What structural abnormality is WPW associated with?

Answer 13

Ebsteins Anomaly

Question 14

WPW

Answer 14

Antegrade conduction down an accessory pathway.

Question 15

What is permanent junctional reciprocating tachycardia?

Answer 15

• Variant of AVRT with orthodromic conduction
  Hallmarks
• Incessant tachycardia (usually slower rate 200bpm)
• Long RP interval
• Inverted P waves inferior leads
  Accessory pathway with slow retrograde conduction
  (decremental)

You see deep inverted P waves in the inferior leads

Question 16

What is AV nodal re-entrant tachycardia?

Answer 16

• Re-entrant circuit within the normal AV node
• Typical or atypical
• Slow pathway and fast pathways (dual AV node physiology)

Question 17

When would you consider giving Verapamil in a child <12months?

Answer 17

Fascicular ventricular tachycardia
Usually more narrow QRS complex with RBBB pattern and superior axis

Question 18

What is Long QT syndrome?

Answer 18

Delayed myocardial repolarisation.

Question 19

What is the channel involved in Long QT 1 and 2?

Answer 19

Potassium channel
One - KCNQ1 - Slow potassium channel low function
Two - KCNH2 - Potassium channel low functioning means it takes longer for potassium to repolarise the cell

Question 20

What is the channel involved in Long QT 3?

Answer 20

Three - SCN5A - Gain of function in sodium channel meaning it stays open causing depolarisation for longer

Question 21

What does the ECG look like in long QT type one?

Answer 21

Broad T wave

Question 22

What does the ECG look like in long QT type two?

Answer 22

Flattened T wave

Question 23

What does the ECG look like in long QT type three?

Answer 23

Peaked T wave that is delayed

Question 24

What is the treatment for long QT syndrome?

Answer 24

Lifestyle modification - reducing adrenaline surges
B blocker - Nadolol (most effective)
Avoid medications that prolong the QT interval eg. ondansetron

Question 25

What gene is involved in Brugada syndrome?

Answer 25

SCN5A - loss of function in the sodium channel

Question 26

Diagnosis of Brugada syndrome?

Answer 26

Diagnosis based on the presence of a spontaneous or drug-induced coved-type ST segment elevation in V1 or V2 (Type 1 morphology) * ST elevation ≥2mm * Gradually descending ST segment * Terminates with negative T wave

Question 27

What is the criteria for rheumatic fever?

Answer 27

Two major or one major and two minor manifestations plus Evidence of a preceding Group A streptococcus infection Major: Carditis (including subclinical evidence of rheumatic valve disease on echocardiogram) Polyarthritis or aseptic mono-arthritis or polyarthralgia Sydenham chorea Erythema marginatum Subcutaneous nodules Minor:Fever ESR ≥30 mm/hr or CPR ≥30 mg/L Prolonged P-R interval on ECG

Question 28

Diagnostic criteria for Kawasaki disease?

Answer 28

Fever for 5+ days Plus 4 of 5 of: No exudative Conjunctival injection (>90%) - perilimbic sparing Mucositis - cracked lips, strawberry tongue Extermity changes (70-98%) - swelling, erythematous, desquamation, beaus lines across finger nails Polymorphous rash - usually maculopapular Cervical lymphadenopathy (25-50%) - >1.5cm

Question 29

How long after IVIG do you need to delay live immunisations for?

Answer 29

11 months

Question 30

Does IVIG cause raised ESR or CRP?

Answer 30

ESR therefore use CRP to monitor inflammatory response

Question 31

What type of medication is sildenofil?

Answer 31

Phosphodiesterase type 5 inhibitor which increased cGMP and nitric oxide causing vasodilation

Question 32

Most common cardiac lesions in 22q11 deletion?

Answer 32

Tetralogy of fallout (35%) Interrupted aortic arch (20%) Truncus arteriosus (10%)

Question 33

What cardiac complication are children with Noonan Syndrome at risk of?

Answer 33

Hypertrophic cardiomyopathy (20%) Up to 50% have pulmonary stenosis

Question 34

What do you see on ECG with hypocalcaemia?

Answer 34

Prolonged QTc

Question 35

What is pulmonary hypertension?

Answer 35

PAP >20mmHg

Question 36

How do you calculate cardiac output?

Answer 36

Qp (Cardiac output)= VO2/ (Sats PV - Sats PA) x Hb x 1.36 Qs = VO2 /(Sats Ao - Mixed venous Sats) x Hb x 1.36 Qp:Qs Aosats - MV sats/PV sats - PA sats

Question 37

What are the ECG findings you would see for a patient with congenitally corrected TGA?

Answer 37

Left axis deviation Deep Q waves V1, II and III, with no Q waves in the left precordial leads V5 and V6. (This indicates abnormal depolarisation of the inter ventricular septum from right to left)