Cardiomyopathy, Restrictive

About 5% of all primary cardiomyopathies.

Idiopathic type is rare, and may be familial.

50% of pts with AL-type amyloidosis are affected.

Endomyocardial fibrosis is endemic in Africa, Asia, and Central and South America.

Diastolic dysfunction and low cardiac output state.

Right heart failure with ascites and congestive hepatomegaly.

Left heart failure with pulmonary edema.

Cardiac arrhythmias, especially atrial fibrillation, ventricular arrhythmias, and AV block.

Thromboembolic complications

Valvular insufficiency

Autonomic neuropathy causing hemodynamic instability

Respiratory, renal, CNS, and airway manifestations of underlying disease.

Heterogeneous group of diseases characterized by restrictive cardiac physiology and diastolic dysfunction.

Cardiac amyloidosis is a disorder of extracellular deposition of proteinaceous material in the myocardium and other organs.

Endomyocardial fibrosis is a restrictive obliterative cardiomyopathy associated with eosinophilia.

Pathophysiology: Increased stiffness of the myocardium that leads to restrictive ventricular filling with elevated filling pressures and dilated atria.

Left ventricular systolic function is usually normal.

Cardiac valves may be affected by infiltrative conditions causing stenosis or regurgitation

Cardiac amyloidosis has a poor prognosis, especially when LVH, reduced systolic function, and heart failure is present.

Primary restrictive cardiomyopathy includes idiopathic (unknown cause) and genetic causes (mutations of sarcomere proteins including troponin I and T).

Secondary restrictive cardiomyopathy occurs as part of a multisystem disorder, which include infiltrative diseases (amyloidosis, sarcoidosis, Gaucher disease), storage diseases (hemochromatosis, Fabry disease, glycogen storage disease), autoimmune disease (scleroderma), endomyocardial disease (carcinoid, endomyocardial fibrosis), and as a sequelae of cancer therapy (radiation therapy, anthracycline).