Abstract 17005: Endomyocardial Biopsies for Diagnostic Evaluation of Specific Cardiomyopathies: A Contemporary Single-Center Experience
Background: Endomyocardial biopsy (EMBx) has been utilized to identify underlying etiologies of specific cardiomyopathies. The evolution of indications and diagnostic outcomes of EMBx in the contemporary era has not been described.
Methods: We reviewed consecutive patients who underwent percutaneous EMBx at the Cleveland Clinic from 1999-2011, and matched suspected etiologies at time of EMBx indication with ultimate pathologic diagnoses.
Results: In our study cohort over 12 years, a total of 587 EMBx were performed, of which 226 (39%) yielded the following specific histopathologic diagnoses: 165 amyloidosis, 21 myocarditis, 18 infiltrative or glycogen storage cardiomyopathies, 5 sarcoidosis, 8 drug toxicity, 9 other cardiomyopathies. In 361 (61%) cases, EMBx was non-specific. Among the 46 EMBx indicated for rule-out acute myocarditis, only 2 (5%) were confirmed, with 4 suggestive of borderline characteristics. Among the 40 cases for rule-out sarcoidosis, only 5 (13%) were confirmed, with 3 had suspicion for sarcoidosis. Among the 326 EMBx indicated for rule-out amyloid heart disease, 165 (51%) were identified to have amyloid present in EMBx. During 2006-11 when histologic analyses were performed for specific subtypes (n=98), there were 40 positive cases for transthyretin amyloid, 38 positive cases for lambda AL amyloid, and 18 positive cases for kappa light chain AL amyloid. In contrast, among the 46 EMBx indicated for suspected myocarditis, only 2 (4%) were confirmed, with 4 displaying suggestive pathologic characteristics. Among the 40 cases referred for possible sarcoidosis, only 5 (12%) were confirmed, with another 3 suggestive but non-specific of sarcoidosis. The patterns of indications for EMBx did not differ between 1999-2005 and 2006-2011 eras.
Conclusion: In our contemporary single-center experience, EMBx had an etiologic diagnostic yield of 38%. EMBx was most often indicated for amyloid heart disease, with over half of the suspected cases being confirmed. Meanwhile, the diagnostic yields for suspected acute myocarditis or sarcoidosis remained relatively lower.
- © 2012 by American Heart Association, Inc.