Genetic cardiology

Question 1

What are the medication causes of left ventricular hypertrophy?

Answer 1

Anabolic steroids
Hydroxychloroquine
Tacrolimus

Question 2

What is the adult diagnostic criteria for HCM?

Answer 2

> 15mm wall thickness in any one myocardial segment not explained by loading conditions

Question 3

What is the differential diagnosis for hypertrophic cardiomyopathy?

Answer 3

1. Sarcomeric Protein Mutation
2. Amyloidosis (AL,TTR)
3. Inborn errors of metabolism
   - Glycogen Storage Disorders
   - Lysosomal Storage Disorders
4. Mitochondrial disorders
   - MELAS, MERFF
5. Neuromuscular Disease (Friedrichs)
6. Malformation Syndromes (Noonans, Leopard)
7. Drug Induced
8. Haemochromatosis

Question 4

What is the echo definition of LVOTO?

Answer 4

Instant peak Doppler LV outflow tract pressure gradient >30mmhg at rest

Question 5

What LVOTO gradient is generally considered to be haemodynamically significant?

Answer 5

> 50mmhg

Question 6

SAM results in mitral regurgitation or what orientation?

Why is this important?

Answer 6

Inferolateral orientation

If regurg jet is oriented centrally or anteriorly, should consider intrinsic mitral valve abnormality

Question 7

In the setting of HCM, what features on echo make amyloidosis more likely?

Answer 7

1. Increased interatrial septal thickness
2. Increased AV valve thickness
3. Rv free wall thickness
4. Pericardial effusion
5. Ground glass myocardium

Question 8

In the setting of HCM, what features on echo make Fabrys disease more likely?

Answer 8

1. Increases AV valve thickness
2. RV free wall thickness
3. Concentric LVH

Question 9

In the setting of HCM, what features on echo make Danon Pompe disease more likely?

Answer 9

1. Extreme concentric LVG >30mm

2. Global LV hypokinesis

Question 10

In the setting of HCM, what features on echo makes Noonans Syndrome more likely?

Answer 10

1. RVOT obstruction

2. RV wall thickness

Question 11

When is septal reduction surgery indicated for patients with HCM?

Answer 11

1. Resting or maximum provoked LVOT gradients >50mmhg who are NYHA class 3-4 despite maximal medical therapy
2. Recurrent exertional syncope causes by LVOT gradient >50mmhg despite optimal medical therapy

Question 12

What factors favour surgical myomectomy over septal alcohol ablation?

Answer 12

1. Other indication for CTSx (mitral valve or pap muscle interventions)
2. Very severe hypertrophy >30mm
3. Extensive septal scarring on CMR

Question 13

When is mitral valve surgery considered in HCM without primary mitral valve disease?

Answer 13

Septal thickness <17mm at pint of mitral leaflet septal contact with LVOT gradient >50mmhg

Question 14

Clinical features that suggest HCM over atheletes heart?

Answer 14

Family history of HCM
Cardiovascular symptoms
Family history of sudden cardiac death <40 years of age

Question 15

Echo features that suggest HCM over atheletes heart?

Answer 15

EDD <45mm 
Raised diastolic indices 
Large LA
Asymmetric hypertrophy 
Hypertrophy >16mm 
(13-16mm is indeterminate)

Question 16

MRI that suggest HCM over atheletes heart?

Answer 16

LGE uptake
Elongation of the mitral valve leaflets
Right ventricular hypertrophy

Question 17

What are the major risk factors for Sudden cardiac death in patients with hypertrophic cardiomyopathy?

Answer 17

Family history of SCD <50 years of age 
Massive LVH >30mm
Episode of likely arrhythmic syncope 
LV EF <50%
Lv apical aneurysm of any size

Question 18

What are the minor risk factors for sudden cardiac death in patients with HCM that may be useful in stratifying risk?

Answer 18

Degree of LGE on CMR (>15%)

Non sustained VT on ambulatory monitoring

Question 19

What is Naxos Disease?

Answer 19

Autosomal recessive condition of the Plano glow in gene characterised by ARVC, woolly hair and palmoplantar keratoderma.

Question 20

What is Carvajal Syndrome?

Answer 20

An autosomal recessive disorder of the desmoplakin gene characterised by LV arrythmogenic cardiomyopathy, woolly hair and palmoplantar keratoderma.

Question 21

According to the current literature, what proportion of ARVC is inherited?

Answer 21

30% though likely underestimated