restrictive cardiomyopathy

Restrictive cardiomyopathy is the least common subtype of cardiomyopathy and is characterized by a marked decrease in ventricular compliance.

Clinical presentation

Patients can present with symptoms and signs of left ventricular failure and/or right ventricular failure .

Pathology

It is predominantly a disease of diastolic dysfunction where the systolic (contractile) of the myocardium is usually unaffected.

Etiology

Recognized causes which can give a restrictive type pattern include:

• cardiac amyloidosis: thought to be the most common cause outside the tropics
• endomyocardial fibrosis: more common in the tropics
• cardiac sarcoidosis
• hemochromatosis
• scleroderma
• radiation therapy
• tumor invasion/infiltration/metastases
• hypereosinophilic (Loffler) syndrome / idiopathic hypereosinophilic syndrome
• drugs:
  • hydroxychloroquine (used to treat SLE and other connective tissue disorders)
  • methysergide
  • anthracyclines
• Anderson-Fabry disease
• glycogen storage diseases
• idiopathic

Radiographic features

Plain radiograph

The heart size can be normal. Sometimes there may be evidence of biatrial dilatation.

Echocardiography

Diastolic dysfunction may be observed with spectral Doppler interrogation of the transmitral filling velocities and tissue Doppler of the mitral annular velocity. The presence of restrictive physiology can be supported with the following:

• transmitral flow velocities
  • amplitude of mitral E wave > 100 cm/s
  • deceleration time (DT) <160 ms
  • ratio between E/A > 2
• tissue doppler imaging of the mitral annulus
  • characteristic, and pathognomic, of restrictive filling physiology is the marked decrease in TDI velocities coupled with brisk reversal of hepatic venous doppler flow upon inspiration
    • an early diastolic (e') septal annular velocity of < 8 cm/s
      • lateral annular e' reduced when < 10 cm/s
    • average E/e' ratio above 13 (using mean of septal and lateral e')
      • correlates with elevated left atrial pressure

Pulmonary venous Doppler may be used as an adjunctive measure in equivocal cases, which should demonstrate:

• reversal of normally systolic dominant filling pattern, with an S/D ratio < 1
• elevation in peak atrial reversal (AR) velocities
  • above 35 cm/s considered elevated

MRI

Cardiac MRI is useful for differentiating between constrictive pericarditis. Biatrial enlargement with minimal or no ventricular enlargement may be present. Cine MRI will show altered diastolic filling.

Differential diagnosis

• constrictive pericarditis: there can be septal flattening on cine MRI and the pericardium can be thicker than 4 mm
• endomyocardial fibrosis: sometimes classified as a restrictive type

Siehe auch:

• Pericarditis constrictiva

und weiter:

• idiopathic hypereosinophilic syndrome
• Kardiomyopathie
• cardiomyopathy 1995 WHO classification
• kardiale Amyloidose