What is the? difference between restrictive cardiomyopathy and constrictive pericarditis?

PERICARDITIS: Pericarditis is inflammation with fluid accumulation and reduced cardiac output. Restrictive cardiomyopathy resist diastolic filling due to noncompliant ventricular walls.

Underlying cause: Clinically similar.Both restricts filling of the ventricles. Although sometimes the echocardiogram and cardiac MRI will show findings favoring one over the other such as a thickened heart,thickened pericardium cardiac catheterization is often required. In restrictive cardiomyopathy the left ventricular pressure is higher than the right specially with fluid challenge.Similarly left atrial pressure

Intrinsic/extrinsic: Restrictive cardiomyopathy involves the heart itself becoming stiff and not filling properly which eventually can cause heart failure and need a transplant to treat. Constrictive pericarditis affects the sac around the heart entrapping the heart and causing similar symptoms but may be treated if needed by removing the sac from around the heart by surgery

Similar but differen: Constrictive pericarditis and restrictive cardiomyopathy both result in diastolic abnomlities of ventricular filling. CP can be thought of as a heart encased in a porcelain shell. In CP the ventricles fill up until the limits of the calcified pericardium (early filling) and then fill no more. In rc the heart is abnormal. Filling throughout diastole is slowed but possible. Doppler can help.