Myocardial Disease - Dilated Cardiomyopathy

Question 1

Pathophysiology of Dilated Cardiomyopathy.

Answer 1

1. Dilated Heart - Predominately Systolic Dysfunction.
2. All 4 Chambers are Dilated (LV Dilation > RV).
3. Eccentric Hypertrophy (Sarcomeres added in Series).

Question 2

Epidemiology of Dilated Cardiomyopathy.

Answer 2

Between 3rd and 6th decades of life.

Question 3

What is Dilated Cardiomyopathy?

Answer 3

Dilation and poor contraction of either the left ventricle or both ventricles, causing an ejection fraction below 40%.

Question 4

Aetiology of Dilated Cardiomyopathy.

Answer 4

1. Idiopathic (Commonest).
2. Myocarditis.
3. Ischaemic Heart Disease & Hypertension.
4. Peripartum.
5. Substance Abuse e.g. Alcohol, Cocaine.
6. Genetic (predisposition or Duchenne Muscular Dystrophy).
7. Infiltrative Diseases e.g. Haemochromatosis, Sarcoidosis.

Question 5

Give a cause that may lead to both dilated cardiomyopathy and restrictive cardiomyopathy.

Answer 5

Nutritional - Wet Beriberi (Thiamine Deficiency).

Question 6

Clinical Features of Dilated Cardiomyopathy.

Answer 6

Heart Failure-Related :

1. Exertion Dyspnoea.
2. Orthopnoea.
3. Paroxysmal Nocturnal Dyspnoea.
4. Peripheral Oedema.

Question 7

Clinical Signs of Dilated Cardiomyopathy.

Answer 7

1. Classic Findings of Heart Failure.
2. Systolic Murmur - Stretching of Valves resulting in Mitral/Tricuspid Regurgitation.
3. S3 Sound - Gallop Rhythm (Rapid Ventricular Filling).

Question 8

CXR Finding in Dilated Cardiomyopathy.

Answer 8

‘Balloon’ Appearance of the Heart on the Chest.

Question 9

ECG Finding of Dilated Cardiomyopathy.

Answer 9

Poor R Wave Progression.