Cardiomyopathy

Question 1

What are the four main types of cardiomyopathy?

Answer 1

• Hypertrophic,
• Dilated (most common)
• Restrictive,
• Arrhythmogenic
  Can also be classficied as priamry, secondary or mixed.

Question 2

What are some causes of dilated cardiomyopathy?

Answer 2

• Idiopathic (most common)
• Alcohol or cocaine
• Myocarditis: Coxsackie B virus, HIV, diphtheria, chagas disease
• IHD, hypertension
• Wet beriberi: Thiamine deficiency
• Peripartum (more common in obese patients),
• Doxorubicin
• Infiltrative (haemochromatosis, amyloidosis and sarcoidosis)
• Thyrotoxicosis

Question 3

What are the signs and symptoms of dilated cardiomyopathy?

Answer 3

Symptoms related to heart failure - Exertional dyspnoea, orthopnea, PND, peripheral oedema.
Common signs - displaced apex beat, S3 gallop rhythm, systolic murmur (regurgitation of AV valves) and balloon appearance of heart of X ray.

Question 4

What are the causes of restrictive cardiomyopathy

Answer 4

• Familial non-infiltrative cardiomyopathy
• Infiltrative: Amyloidosis, sarcoidosis, Gaucher disease (lipid accumulation), Hurler syndrome or fatty infiltration.
• Storage: Haemochromatosis, fabry disease
• Others: Diabetic cardiomyopathy, scleroderma, Loeffler’s syndrome (hyperesosinophilic syndrome), radiation or chemotherapy

Question 5

What are the signs and symptoms of restrictive cardiomyopathy?

Answer 5

• Similar to heart failure and constrictive pericarditis.
• RV failure symptoms due to reduced venous return.
• Commonly have Af

Question 6

What is arrhythmogenic right ventricular cardiomyopathy?

Answer 6

It is caused by fatty fibrous material replacing the myocardium. Caused by genetic defect in desmosomes. It causes palpitations, syncope and sudden cardiac death

Question 7

What is Takotsubo cardiomyopathy?

Answer 7

Apical ballooning of the myocardium usually triggered by extreme stress.
Suspect in patients with trop positive chest pain and history of significant stressor. DO ECHO

Question 8

What are some neuromuscular conditions which cause cardiomyopathy?

Answer 8

• Fredreich’s ataxia,
• Duchenne-becker muscular dystrophy,
• Myotonic dystrophy

Question 9

What is hypertrophic obstructive cardiomyopathy and its features

Answer 9

• Autosomal dominant condition which causes mutation in gene encoding beta-myosin heave chain protein or myosin binding protein C.
• It results in diastolic dysfunction, left ventricular hypertrophy and decreased cardiac output

Question 10

What are the signs and symptoms of HOCM?

Answer 10

Often asymptomatic but can present with:
- Exertional dyspnoea, angina, syncope (typically following exercise as subaortic hypertrophy of ventricular septum results in function aortic stenosis),
- Sudden death most commonly due to ventricular arrhythmias
- Heart failure
- Systolic murmurs,
- Jerky pulse

Question 11

What is HOCM associated with?

Answer 11

Friedrich’s ataxia and Woldd-Parkinson White syndrome

Question 12

What are the ECHO findings for HOCM

Answer 12

MR SAM ASH - definitive diagnosis
- Mitral Regurgitation
- Systolic Anterior Motion of mitral valve leaflets.
- Asymmetrical septal hypertrophy

Question 13

What is the management of HOCM?

Answer 13

ABCDE
- Amiodarone,
- Beta blockers or verapamil for symptoms
- Cardioverter defibrillator
- Dual chamber pacemaker
- Endocarditis prophylaxis

Avoid ACE inhibitors and nitriates as it can worsen things

Question 14

What drugs should be avoided in HOCM

Answer 14

Nitrates, ace inhibitors and ionotrophes

Question 15

What is WPW?

Answer 15

Arrhythmia caused by congenital accessory pathway leading to atrio-ventricular re-entry tachycardia

Question 16

What are the ECG findings of WPW?

Answer 16

Short PR interval
Wide QRS with slurred upstroke (delta wave)
Left axis deviation (if right sided pathway)
Right axis deviation (if left sided pathway)