Inherited Cardiac Conditions

Question 1

What types of inherited cardiac conditions are there?

Answer 1

DNA mutations, cardiomyopathy, channelopathy, aortopathy

Question 2

What is cardiomyopathy?

Answer 2

Heart muscle abnormality

Question 3

Examples of cardiomyopathy

Answer 3

Arrhythmogenic right ventricular cardiomyopathy, hypertrophic cardiomyopathy, dilated cardiomyopathy

Question 4

What is channelopathy?

Answer 4

Heart rhythm abnormalities

Question 5

Examples of channelopathy

Answer 5

Long QT syndrome, Brugada syndrome, short QT syndrome, familial AF, familial QPQ, catecholaminergic polymorphic ventricular tachycardia

Question 6

What is arteriopathy?

Answer 6

Arterial blood vessel abnormality

Question 7

Examples of arteriopathy

Answer 7

Marfans syndrome, Ehlers Dalos syndrome

Question 8

Symptoms related to channelopathies

Answer 8

Palpitations, fast heartbeat, faints, breathlessness, chest pain

Question 9

Symptoms related to cardiomyopathies

Answer 9

Breathlessness, swollen legs, weakness

Question 10

Channelopathies:

• Where is the mutation?
• What part of the cardiac conduction cycle does it mainly affect?
• ECG
• Structure and function

Answer 10

• Genes that code the cardiac ion channels
• Mainly affects repolarisation
• Changes on an ECG
• Normal structure and function

Question 11

Congenital long QT syndrome:

• ECG changes
• Where is the mutation?
• Hallmark arrhythmia and other associated arrhythmias
• Primary presenting complaint

Answer 11

• QT interval prolongation >440ms in males, >450ms females
• Mutation in potassium channel
• Torsades de pointes is the hallmark arrhythmia but also associated with AF, heart block
• Syncope, sudden cardiac death in children and young adults

Question 12

Triggers of torsades de pointes syncope

Answer 12

Exercise, sudden auditory stimuli, sleep, QT prolonging states (medication, hypokalaemia)

Question 13

Management of congenital long QT syndrome

Answer 13

Beta-blockers, avoid QT prolonging drugs, avoidance of triggers (strenuous swimming, loud noises, breath holding), correction of electrolyte abnormalities

Question 14

Brugada syndrome:

• Where is the mutation?
• Risk of which arrhythmias?
• Other ECG changes
• Autosomal resistant or autosomal dominant?
• Which gender does it occur most commonly in?

Answer 14

• Sodium channel mutation
• Risk of polymorphic VT/VF, AF is common
• ST elevation and RBBB in leads V1-V3
• Autosomal dominant
• Males

Question 15

Triggers of VF

Answer 15

Rest or sleep, fever, excessive alcohol, large meals

Question 16

Management of Brugada syndrome

Answer 16

Avoidance of drugs that may induce Brugada changes, avoidance of alcohol and large meals, prompt treatment of fever, ICD if ventricular arrhythmia

Question 17

Drugs to avoid in Brugada syndrome

Answer 17

Anti-arrhythmic drugs, psychotropics, analgesics, anaesthetics

Question 18

Where is the mutation in hypertrophic cardiomyopathy?

Answer 18

Sarcomeric genes

Question 19

Hypertrophic obstructive cardiomyopathy clinical presentations

Answer 19

Sudden death, heart failure, angina, AF, asymptomatic

Question 20

Management of inherited cardiac conditions:

• Diagnosis
• Risk management

Answer 20

Diagnosis - clinical testing and genetic testing
Risk management - lifestyle modification, pharmacological, non-pharmacological intervention
Family screening is important

Question 21

Diet changes in long QT syndrome

Answer 21

Potassium rich foods (bananas, beans, oranges, green leafy veg, nuts)

Question 22

Which medications should be avoided in long QT syndrome

Answer 22

Antidepressants, antibiotics, antihistamines

Question 23

Subcutaneous implantable cardioverter-defibrillator benefits

Answer 23

Prevention of vascular complications, better cosmetic and functional outcome, lead extraction safe

Question 24

Transvenous implantable cardioverter-defibrillator disadvantages

Answer 24

High risk of vascular and cardiac complications in lifetime, cosmetic and functional issues related to ICD position e.g. seatbelts, shoulder bags, lead extraction has high risk of morbidity and mortality

Question 25

Implantable cardioverter-defibrillator issues in the young

Answer 25

Psycho-social impact, lifestyle (school, sports, pregnancy, ICD therapy, employment, life-insurance