RESTRICTIVE CMP

Characterized by abnormal diastolic relaxation, often with mildly reduced systolic function. Etiologies include infiltrative disease (e.g., amyloidosis, sarcoidosis), storage diseases (hemochromatosis, Fabry’s disease), fibrotic disorders (radiation, scleroderma), endomyocardial disease (hypereosinophilic syndrome, endomyocardial fibrosis).

SYMPTOMS

Exercise intolerance, then symptoms of heart failure, often predominantly right-sided.

PHYSICAL EXAMINATION

Especially signs of right-sided heart failure: JVD (Kussmaul sign may be present), hepatomegaly, peripheral edema. S4 is common.

LABORATORY ECG

Low limb lead voltage (e.g., in some forms of amyloidosis), sinus tachycardia, ST-T-wave abnormalities.

CXR

Mild LV enlargement.

ECHOCARDIOGRAM, CT, CARDIAC MRI, NUCLEAR IMAGING

Bilateral atrial enlargement, often to a marked degree; increased ventricular thickness (“speckled pattern”) common in infiltrative disease, especially amyloidosis. Systolic function is usually normal or mildly reduced. Doppler analysis shows impaired diastolic function. Amyloid infiltration can be detected with MRI gadolinium enhancement. Technetium pyrophosphate nuclear imaging is sensitive for detection of transthyretin amyloidosis.

CARDIAC CATHETERIZATION

Increased LV and RV diastolic pressures with “dip and plateau” pattern; RV biopsy useful in detecting infiltrative disease.
Note: Must distinguish restrictive CMP from constrictive pericarditis, which is surgically correctable. Thickening of pericardium on CT or MR imaging is apparent in >80% of pts with constrictive pericarditis.

Treatment: Restrictive CMP

Salt restriction and diuretics ameliorate pulmonary and systemic congestion.
Note: Increased sensitivity to digitalis in amyloidosis. Anticoagulation often indicated, particularly in pts with eosinophilic endomyocarditis. For specific therapy of amyloidosis, hemochromatosis and sarcoidosis, see Chaps. 108, 407 and 360, respectively, in HPIM-20.

Outline

RESTRICTIVE CMPis the Harrison's Manual of Medicine Word of the day!