The Role Of Endomyocardial Biopsy In The Diagnosis Of Unexplained Heart Failure

Objective: To evaluate the clinical value of endomyocardial biopsy (EMB) in the diagnosis of unexplained heart failure.Methods: The clinical data, including electrocardiograph, echocardiography data and EMB results from 41 patients with heart failure of unknown origin were analyzed. All the patients underwent EMB in the Department of Cardiology, Peking Union Medical College Hospital from Aug 2006 to March 2009. Pathological examinations including HE staining, PTAH staining, Masson staining, Congo staining were performed.Immunohistochemistry test was added if amyloid cardiomyopathy was suspected. Definition and classification of cardiomyopathy was based on the 2007 Position Statement from the European Society of Cardiology Working Group on Myocardial and Pericardial DiseasesResults: Forty one patients were included in the study, including 31 male, and 10 female. The mean age was 41.8 years (14 to 65 years). All patients were divided into 4 groups: Restrictive Cardiomyopathy in 16 patients; Dilated Cardiomyopathy in 15 patients; Hypertrophic Cardiomyopathy in 3 patients; and Unclassified Cardiomyopathy in 7 patients. Among 16 patients of restrictive cardiomyopathy, 9 were confirmed as amyloid cardiomyopathy by EMB. Of 15 cases of dilated cardiomyopathy, infiltration of neutrophil and lymphocytes was found in the EMB specimens in 2 cases of Polymyositis/Dermatomyositis (PM/DM) with heart involvement. Patients diagnosed as myocarditis, anthracycline cardiomyopathy, peripartum cardiomyopathy, isolated left ventricular noncompaction and alcoholic cardiomyopathy had negative EMB results. One of the 3 hypertrophic cardiomyopathy patients was finally diagnosed as cardiac involvement of Danon's disease according to the EMB result. EMB made the final diagnosis in 2 cases of unclassified cardiomyopathy.Conclusions: EMB may play an important role in the diagnosis of restrictive cardiomyopathy, especially cardiac amyloidosis. EMB may also uncover some of the pathological features, which may represent characteristics of the underline diseases. Further studies are needed to validate the value of EMB in differentiating the primary from secondary involvement of heart.