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• Cardiomyopathy


  Abnormal structure and function of myocardium (specific heart disease)
• Cardiomyopathy is a condition where the myocardium is involved, unlike myocarditis which affects the heart muscle
• Primary cardiomyopathy


  • Refers to heart disease (including unexplained causes) that originates from the heart muscle rather than from other diseases
• Secondary (specific) cardiomyopathy


  • The etiology has been identified or is part of a systemic disease
• Types of primary cardiomyopathy


  • Dilated cardiomyopathy (DCM)
  • Hypertrophic cardiomyopathy (HCM)
  • Restricted cardiomyopathy (RCM)
  • Arrhythmogenic right ventricular cardiomyopathy (ARVC)
  • Unclassified cardiomyopathy (UCM)
• Diagnostic methods for cardiomyopathy


  • ECG
  • Biochemical markers of myocardial injury
  • Echocardiography
  • Cardiac MRI
  • Endomyocardial biopsy
• Prognosis of cardiomyopathy


  • Almost myocarditis is self-limiting without any obvious symptom
  • Death may occur due to a ventricular arrhythmia or rapidly progressive heart failure for some severe cases
  • Hypertrophic cardiomyopathy (HCM)
  • Arrhythmogenic right ventricular cardiomyopathy (ARVC)
  • Dilated cardiomyopathy (DCM)
  • Restricted cardiomyopathy (RCM)
  • VF/VT
  • HF
• Dilated cardiomyopathy (DCM)


  A complex cardiomyopathy caused by hereditary and non-hereditary causes, characterized by enlargement of left ventricle, right ventricle or biventricular chamber and dysfunction of contraction
• DCM is usually diagnosed by 2-dimensional echocardiography, with increased left ventricular mass but normal or reduced wall thickness
• The main clinical manifestations of DCM are decreased left ventricular systolic function, progressive heart failure, combined with ventricular and supraventricular arrhythmias, conduction abnormalities, thromboembolism and sudden death
• The United States has 365/100,000 DCM and China has 19/100,000 DCM. One fourth of heart failure is caused by DCM. The 5-year mortality rate is as high as 15-50%
• Causes of DCM


  • Persistent viral infection
  • Family hereditary DCM
  • Alcoholic cardiomyopathy
  • Infection/immune DCM
  • Toxic DCM
  • Perinatal cardiomyopathy
  • Tachycardiac cardiomyopathy
  • Metabolic endocrine and nutritional diseases(beriberi)
• Pathology of DCM (macroscopic)


  • The heart is generally enlarged, usually both left and right ventricular chambers are enlarged and dilated, mainly the left ventricle
  • It may be accompanied by calcification, endocardial thickening and fibrosis
  • Muscular thrombosis is mostly at the apex of the heart chamber
  • Thinning of ventricular wall
• Pathology of DCM (microscopic)


  • Interstitial and perivascular fibrosis is widespread, and myocardial fibers are coarsened, degenerated, ruptured or necrotic
  • A small amount of inflammatory cell infiltration
• Pathophysiology of DCM


  1. Heart pump dysfunction

  2. Myocardial interstitial fibers ↑ → myocardial contractility ↓ → cardiac stroke volume ↓ → cardiac exclusion volume ↓ → cardiac blood storage(preload) ↑ → cardiac enlargement

  3. Bilateral ventricular dilatation, usually left ventricular dilatation (left ventricular type) ; a few right ventricular dilatation (right ventricular type) → eventual congestive heart failure

  4. Early stage: Heart rate ↑ → to maintain adequate cardiac output(CO)

  5. Late stage: cardiac stroke volume and cardiac output ↓ → left ventricular diastolic and end-systolic residual blood volume ↑ → progressive heart cavity ↑ → mitral and tricuspid insufficiency (relativity) → congestive heart failure
• Clinical manifestations of DCM


  • Slow and gradual onset at age of 30-50 years old
  • Family hereditary DCM occurs more earlier( most young)
  • Pulmonary and systemic circulation congestion
  • With various arrhythmias, embolism (18%) or sudden death (30%)
  • Enlargement of the heart
  • S1 low bluntness, S3 and/or S4Running Horse Rhythm and Various Types of Arrhythmia
  • Systolic murmur can be heard in mitral or tricuspid regions
  • Signs of circulatory congestion: Edema, congestion of liver
• Echocardiographic characteristics of DCM


  • Whole heart enlargement, especially left ventricular enlargement. Left ventricular outflow tract enlargement
  • Diffuse weakening of ventricular septum and left ventricular wall motion
  • The apex of the heart is prone to wall mass echoes
  • Relative valvular insufficiency and characteristic changes of small and large heart valves are common
  • The thickness of the interventricular septum and the posterior wall of the left ventricle is normal, but it is thinner than the enlarged left ventricle
  • Left ventricular end-diastolic diameter > 2.7 cm/m2, end-diastolic solvent > 80 ml/m2, suggesting ventricular enlargement
• Echocardiographic characteristics of DCM

  • Big, thin, weak, small
• Left ventricular thrombosis is common in DCM, often seen at the apex of the ventricle
• Other diagnostic tests for DCM


  • ECG
  • X-ray examination
  • Endocardial myocardial biopsy
  • Cardiac catheterization
  • Radionuclide imaging
  • Immunological examination
  • Gene examination
• Other diseases causing myocardial damage should be excluded in the differential diagnosis of DCM
• Treatment objectives for DCM


  • Preventing myocardial damage mediated by underlying causes: alcohol
  • Effective control of heart failure and arrhythmia
  • Prevention of sudden death and embolism: ICD and anticoagulation
  • Improving the quality of life and survival rate
• Treatment principles for DCM


  • Life style: properly restrict physical activity and eat a low-salt diet
  • Diuretics
  • B-R blockers
  • ACE inhibitor and ARB is predominant
  • Digitalis: more easily poisoned by digitalis, use cautiously
  • Cardiocardioverter defibrillator
  • Cardiac synchronization therapy for HF with CLBBB patient
  • Left ventricular assist device
  • Heart transplantation
• The duration of DCM varies, the frequency of congestive heart failure is high, and the prognosis is poor
• Dilated cardiomyopathy (DCM) treatment


  • Prevention of sudden death and embolism: ICD and anticoagulation
  • Improving the quality of life and survival rate
• Treatment of DCM


  1. Life style: properly restrict physical activity and eat a low-salt diet

  2. Diuretics

  3. B-R blockers

  4. ACE inhibitor and ARB is predominant

  5. Digitalis: more easily poisoned by digitalis, use cautiously
• Beta-receptor blockers in DCM treatment


  • The B-blockers that are beneficial are carvedilol, metoprolol and bisoprolol
  • Start with a small dose and double the dose in 2-4 weeks
  • Target heart rate is not less than 55 beats/divided into target dose or maximum tolerance doses
  • Bronchospasm and conduction block are contraindications
• Additional DCM treatments


  1. Cardiocardioverter defibrillator

  2. Cardiac synchronization therapy for HF with CLBBB patient

  3. Left ventricular assist device

  4. Heart transplantation
• The duration of DCM is variable, the frequency of congestive heart failure is high, and the prognosis is poor. The 5-year mortality rate was 35%, and the 10-year history rate was 70%
• Causes of sudden death in DCM: ventricular arrhythmias (especially ventricular fibrillation)
• The main causes of death in DCM were heart failure and severe arrhythmia
• Hypertrophic cardiomyopathy (HCM)


  A cardiomyopathy with a certain hereditary tendency, characterized by asymmetric cardiac hypertrophy, diminished ventricular chamber, obstruction of left ventricular blood filling and decline of diastolic compliance
• Types of hypertrophic cardiomyopathy


  • Obstructive hypertrophic, also known as hypertrophic and outflow tract stenosis
  • Non-obstructive hypertrophic cardiomyopathy
• Hypertrophic cardiomyopathy is one of the common causes of sudden death in young population
• Epidemiology of hypertrophic cardiomyopathy


  • Prevalence rate 180-200/100,000
  • The onset is often slow and the natural course can be long. The highest age is 90 years old and 23% is over 75 years old
  • About a third of them have family history. Men and women suffer from the same disease
  • Symptoms mostly begin before the age of 30
  • The peak age of death was 4-6% in children and adolescents
• The main causes of death of HCM were sudden cardiac death (51%), heart failure (36%) and stroke (13%)
• 16% of sudden deaths in HCM occur during moderate to extreme physical activity
• Causes of HCM


  • Family history is often evident (1/3-1/2)
  • Autosomal dominant inheritance: myocardial sarcomere protein gene mutation
  • The etiology of 1/2 patients is unknown
• Fifteen genes and more than 400 mutations have been identified to be associated with HCM
• Pathology of HCM (naked eye)


  • Myocardial hypertrophy and ventricular contraction
  • Left ventricular hypertrophy is common, often accompanied by mitral valve thickening