Inherited Cardiac Conditions

Question 1

What are the three main types of inherited cardiac conditions?

Answer 1

Cardiomyopathies –> heart muscle
Channelopathies –> heart rhythm
Aortopathies –> arterial blood vessels

Question 2

Give some examples of cardiomyopathies

Answer 2

Hypertrophic cardiomyopathy
Dilated cardiomyopathy
Restrictive cardiomyopathy
Arrhythmogenic RV cardiomyopathy

Question 3

Give some examples of channelopathies

Answer 3

Long QT syndrome

Brugada syndrome

Question 4

Give two examples of aortopathies

Answer 4

Marfan’s

Ehlers Danlos

Question 5

What causes channelopathies?

Answer 5

Mutations in genes that encode cardiac ion channels

–> propensity to develop arrhythmias

Question 6

What does long QT syndrome look like on an ECG?

Answer 6

QTc interval prolongation

• > 440ms in men
• > 450ms in women

Question 7

What in the hallmark arrhythmia that develops from long QT syndrome?

Answer 7

Polymorphic VT

Question 8

What is another name for polymorphic VT?

Answer 8

Torsades de Pointes

Question 9

Give some examples of triggers for VT onset in long QT syndrome

Answer 9

• exercise
• sleep
• sudden auditory stimuli
• medication
• hypokalaemia (prolongs QT)

Question 10

How is congenital long QT syndrome managed?

Answer 10

Treat with beta-blockers
Avoid triggers and QT prolonging drugs
Maintain K+ at upper limit of normal –> eat potassium rich foods

Question 11

Which arrhythmias does Brugada syndrome predispose to?

Answer 11

VT, VF or AF

Question 12

Which ECG changes are seen in Brugada syndrome?

Answer 12

ST elevation + RBBB in V1 - V3

Question 13

What are the triggers for VT in Brugada syndrome?

Answer 13

Usually rest/sleep
Fever
Excessive alcohol
Large meals

Question 14

What is the management of Brugada syndrome?

Answer 14

Avoidance of drugs e.g. AADs, psychotropics, analgesics, anaesthetics
Avoid alcohol and large meals
Prompt treatment of fevers
ICD if ventricular arrhythmia

Question 15

What does the heart look like in dilated cardiomyopathy?

Answer 15

Dilated, huge, flabby

Question 16

What are some of the associations with dilated cardiomyopathy?

Answer 16

Congenital (X linked)
Alcohol
Hypertension
Haemochromatosis
Viral infection
Autoimmunity
Peri/postpartum
Thyrotoxicosis

Question 17

Which symptoms are seen in dilated cardiomyopathy?

Answer 17

Fatigue
SOB
–> heart failure

Question 18

Which signs might be evident in dilated cardiomyopathy?

Answer 18

Tachycardia
Hypotension
Raised JVP
Displaced apex
S3 gallop rhythm
Mitral or tricuspid regurgitation
Pleural effusion
Oedema
Jaundice/hepatomegaly
Ascites

Question 19

Which investigations should be done in dilated cardiomyopathy and what might be found?

Answer 19

Raised BNP
CXR –> cardiomegaly, pulmonary oedema
Echo –> dilated heart, reduced ejection fraction

Question 20

What is the leading cause of sudden cardiac death in young people, often athletes?

Answer 20

Hypertrophic cardiomyopathy

Question 21

What is the pathophysiology in hypertrophic cardiomyopathy?

Answer 21

LV outflow tract obstruction due to asymmetrical septal hypertrophy
–> heart cannot relax during diastole

Question 22

How might the pulse be described in someone with hypertrophic cardiomyopathy?

Answer 22

Jerky

Question 23

What would the Echo show in someone with hypertrophic cardiomyopathy?

Answer 23

Asymmetrical septal hypertrophy

Question 24

Which cardiac abnormalities are associated with Marfan’s syndrome?

Answer 24

Aortic root dilatation –> aortic regurgitation
Mitral valve prolapse and mitral regurgitation
Risk of aortic dissection

Question 25

Which cardiac abnormalities are associated with Turner’s syndrome?

Answer 25

Coarctation of the aorta
Aortic stenosis
Bicuspid aortic valve
Aortic dilatation and dissection

Question 26

Which cardiac abnormalities are associated with congenital rubella syndrome?

Answer 26

PDA
Atrial septal defect
Pulmonary stenosis