FN: Bradycardias

Question 1

Causes

Answer 1

DIVISIONS
Drugs
Ischaemia
Vagal hypertonia
Infection
Sick sinus syndrome
Infiltration
O
Neuro
Septal defect
Surgery or catheterisations

Question 2

Drugs

Answer 2

Antiarrhythmics (type 1a, amiodarone)
Beta-blockers
Calcium channel blockers (verapamil
Digoxin

Question 3

Ischaemia/infarction

Answer 3

Inferior MI

Question 4

Vagal hypertonia

Answer 4

Athletes
Vasovagal syndrome
Carotid sinus syndrome

Question 5

Infection

Answer 5

Viral myocarditis
rhuematic fever
Infective endocarditis

Question 6

Sick sinus syndrome

Answer 6

structual damage or fiboris of SAN, AVN or conducting tissue

PC: SVT alternating with either sinus brady ± arrest or SA/AV block

Question 7

Infiltration

Answer 7

Restrictive/dilated cardiomyopathy

1. autoimmune
2. Sarcoid
3. haemochromatosis
4. amyloid
5. muscular dystrophy

Question 8

O

Answer 8

hypOthyroidism
HypOkalaemia (or hyper)
HypOthermia

Question 9

Neuro

Answer 9

Raised ICP

Question 10

Septal defect

Answer 10

Primum ASD

Question 11

Sick sinus syndrome Rx

Answer 11

Bradyarythmias: pace
Tachyarrythmias: amiodarone

Question 12

Classification

Answer 12

Sinus brady
First dgeree heart block: PR >200ms
Secondar degree:
1. Wenkebach/mobitz I
2. Mobitz II

Complete heart block

1. Junctional:narrow QRS @ 50bpm
2. VentricularL broad QRS @ 40 bpm

Question 13

Rx of Brady

Answer 13

If asymptomatic and rate >40:no Rx needed

Question 14

Urgent Rx/rate

Answer 14

Treat underlying cause e.g. drugs, MI

2. Medical
   - -> atropine 0.6-1.2g (max 3g) IV
   - -> Isoprenaline IVI
3. Pacing: external

Question 15

Elective RX and in which conditions

Answer 15

Permanent pacing:

1. Mobitz II
2. Complete AV block
3. sick sinus
4. AF
5. Drug resistant tachyarrhythmias