Cardiomyopathies

Question 1

What are the main types of cardiomyopathies?

Answer 1

• Primary - involving the heart.
• Genetic
  
  • HOCM & Arrhythmogenic right ventricular dysplasia - Both AD.
• Mixed - Dilated vs Restrictive.
• Acquired - Peripartum or Takotsubo
• Secondary cardiomyopathies - part of a generalized systemic disorder.

Question 2

What are the two main genetic cardiomyopathies and how are they inherited?

Answer 2

• HOCM
• Arrhythmogenic right ventricular dysplasia

Both are inherited as AD

Question 3

What causes HOCM?

Answer 3

A mutation in the gene encoding B-myosin heavy cain protein

Question 4

What are some common ECHO findings in HOCM?

Answer 4

• MR
• Systolic anterior motion (SAM) of the anterior mitral valve
• Asymmetric septal hypertrophy

Question 5

What is the pathology of arrhythmogenic right ventricular dsplasia?

Answer 5

• Right ventricular myocardium is replaced by fatty and fibrofatty tissue.
• 50% have a mutation in the genes which make desmosomes.

Question 6

What ECG findings are seen in arrhythmogenic right ventricular dsplasia?

Answer 6

V1-V3 show T-wave inversion.

Question 7

What are the classical causes of dilated cardiomyopathy?

Answer 7

• Alcohol
• Coxsackie B virus
• Wet beri beri
• Doxorubicin

Question 8

What are the classical causes of restrictive cardiomyopathy?

Answer 8

• Amyloidosis
• Post-radiotherapy
• Loeffler’s endocarditis

Question 9

What are the two types of acquired cardiomyopathy?

Answer 9

• Peripartum cardiomyopathy
• Takotsubo’s cardiomyopathy

Question 10

When does peripartum cardiomyopathy usually occur?

Answer 10

In the last month of pregnancy and 5 months post-partum

Question 11

In what women is peripartum cardiomyopathy more common in?

Answer 11

• Older women
• Greater partiy
• Multiple gestations

Question 12

What goes on in Takotsubo Cardiomyopathy?

Answer 12

Stress induced cardiomyopathy

(patient finds out their family member dies and develops chest pain and features of heart failure)

NOTE: Coronary artery vasospasm is similar but w/o signs of heart failure.

Question 13

Name some secondary causes of cardiomyopathy?

Answer 13

• Infective - Coxsackie B virus, Chagas.
• Storage - Haemochromatosis
• Endocrine - T2DM, Thyrotoxicosis, Acromegaly
• Granulomatous - sarcoidosis
• Neuromuscular -
  
  • Duchenne-Becker muscular dystrophy
  • Myotonic dystrophy
• Nutritional - Beri beri (thiamine deficiency)
• Autoimmune - SLE