Controversial issues in restrictive cardiomyopathy.

The topic of restrictive cardiomyopathy remains controversial for many reasons. The term cardiomyopathy is unfortunately sometimes used interchangeably with diastolic heart failure. Furthermore, diastolic heart failure is sometimes linked with other causes of diastolic dysfunction such as hypertrophic cardiomyopathy and mitral valve disease. Restrictive cardiomyopathy is a clinical entity of primary or secondary myocardial disease presenting a picture that closely simulates that of constrictive pericarditis. In the majority of cases the correct diagnosis can be arrived at following a careful paradigm that begins with history and may end with endomyocardial biopsy. Many of the old teachings about how to distinguish restrictive cardiomyopathy from constrictive pericarditis have not held up with time and clinical experience: in particular equal diastolic pressures on both sides of the heart are compatible with either restrictive cardiomyopathy or constrictive pericarditis.