Cardiomyopathy

Question 1

classification of cardiomyopathy

Answer 1

Dilated cardiomyopathy
Hypertrophic cardiomyopathy

Restrictive cardiomyopathy

Arrhythmogenic RV cardiomyopathy

(Unclassified)

Question 2

cardiomyopathies

Answer 2

Question 3

hypertrophic cardiomyopathy

Answer 3

Genetic cardiac disease [AD]
Incidence 1:500
Variable genetic, structural, clinical expression
Asymmetric LVH
Variable site
Variable severity
Differential diagnosis: AS, sub-AS, LVH …, athletes heart

Question 4

sarconmere mutations in HCM

Answer 4

Beta myosin heavy chain (35%)

Myosin-binding protein C (15%)

Troponin T (15%)

alpha-Tropomyosin (5%)

Myosin light chain (1%)

Cardiac contraction occurs when calcium binds the troponin complex (subunits C, I, and T) and alpha-tropomyosin. Actin stimulates ATPase activity in the globular myosin head and results in the production of force along actin filaments. Cardiac myosin-binding protein C binds myosin and modulates contraction. In hypertrophic cardiomyopthy, mutations may impair these and other protein interactions, result in ineffectual contraction, and produce hypertrophy. Percentages represent the estimated frequency with which a mutation causes hypertrophic cardiomyopathy

Question 5

hcm history

Answer 5

Dyspnoea/fatigue
i.e. heart failure symptoms

Angina
normal coronary arteries

Palpitations/collapse

Family history

Question 6

hcm examination

Answer 6

Cardiomegaly
Apical systolic thrill/heave
Brisk/jerky carotid pulse
S4
Ejection systolic murmur
(increase with Valsalva, GTN, exercise)

Question 7

hcm ecg

Answer 7

Q waves
LVH
Abnormal ST Segments
T wave inversion

Question 8

echo hcm

Answer 8

LVH
LVOT obstruction
Exclude AS etc

Question 9

scd

Answer 9

Commonest cause of SCD in young

Frequently exertional (sport)

Ventricular tachyarrhythmias

• Disorganised myocyte architecture
• Microvascular abnormalities
• Ischaemic bursts
• Replacement scarring

High risk: ICD

• VT
• FHx SCD
• decrease BP
• increase LVH

Question 10

scd treatment

Answer 10

Symptoms
Beta blockers
Verapamil
Disopyramide
Septal ablation
Myectomy MV repair/replacement

Risk
ICD
Avoid exercise

Question 11

dilated cardiomyopathy

Answer 11

Cardiac enlargement and systolic dysfunction

Common (25%) cause of heart failure

Idiopathic (>50% cases)

• Genetic factors/family history
• Viral myocarditis
• Immunological abnormalities

Identifiable cause in <50% …

Question 12

dilated cardiomyopathy history

Answer 12

Heart failure

• Dyspnoea
• Fatigue
• Fluid congestion

systemic emboli

Family history
Viral illness
Other causes

Question 13

DCM examination

Answer 13

Fluid congestion
- Raised JVP, ankle oedema

Cardiomegaly

S3, S4

Secondary MR, TR

Other causes*

Question 14

HCM investigation

Answer 14

ECG (non-specific)

• ST, T wave changes
• SVT, VT
• Heart block

CXR (non-specific)

• Cardiolomegaly
• Pulmonary venous congestion/oedema

Blood/other tests (specific)
- E.g. Iron, Copper, thyroid, B12

Question 15

HCM treatment

Answer 15

Heart failure Rx
ACE inhibitors, beta blockers, diuretics
Device therapy
Biventricular pacing, ICD
Cardiac transplantation

Question 16

restrictive cardiomyopathy

Answer 16

Group of heart muscle disorders characterised by …
Thickened, “stiff” myocardium
Reduced LV compliance
Diastolic dysfunction
±“systolic function” preserved

PRIMARY restrictive cardiomyopathy
SECONDARY …

Question 17

restrictive crdiomyoparthy

Answer 17

Question 18

history of rwstrictive

Answer 18

Congestive heart failure

• Dyspnoea, fatigue
• Fluid congestion

Symptoms of systemic disease (eg amyloid)

Question 19

restrictive examination

Answer 19

Mild cardiomegaly
S3 or S4
increase JVP

Question 20

restrctive ecg

Answer 20

Low voltages (despite thick myocardium)
 Heart block

Question 21

restrictive echo

Answer 21

Small ventricular cavities
Ventricular hypertrophy
(impaired contraction)
Abnormal myocardial texture
increase thickness atrial septum, valves
Bi-atrial enlargement

Question 22

hypereosiniphilic heart disease (RCM) - Loeffler’s endocardial fibrosis

Answer 22

response to 1º or 2º eosinophilia

direct toxic effect on endocardium

• free radical mediated
• inflammatory phase: myocarditis
• thrombotic phase
• fibrotic phase: “RCM”

Question 23

rcm treatment

Answer 23

Heart failure drugs

Specific therapies

• E.g. Hypereosinophilic RCM
• Warfarin
• Steroids

Question 24

arrythmogenic RV cardiomyopathy

Answer 24

Rare, familial

Diffuse/segmental RV…

• Myocyte death
• Fibrous/fatty replacement
• Myocarditis

RV (LV) enlargement
- Systolic dysfunction

Ventricular arrhythmia
- May be presenting feature

Question 25

ARVC gives an epsilon wave

Answer 25

Question 26

ARVC echo and mri

Answer 26

Focal/diffuse RV…

• echodensity
• dilatation
• dysfunction

Question 27

ARVC treatmenr

Answer 27

Avoid exercise (sport)
Defibrillator
Family screening