Dilated Cardiomyopathy - Biopsy Diagnosis

2/12/2003

Question: What is the role of endomyocardial biopsy in the etiologic diagnosis of cardiomyopathy?

Link Directly to Fulltext article in Ovid

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Unique Identifier:11605687

Authors: Wu LA. Lapeyre AC 3rd. Cooper LT.

Institution: Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, Rochester, Minn 55905, USA.

Title: Current role of endomyocardial biopsy in the management of dilated cardiomyopathy and myocarditis. [Review] [81 refs]

Source: Mayo Clinic Proceedings. 76(10):1030-8, 2001 Oct.

Abstract: Dilated cardiomyopathy is a common cause of congestive heart failure. Despite a thorough cardiovascular evaluation, a specific cause is frequently not found, and the disorder then is considered idiopathic. Endomyocardial biopsy (EMB) may yield diagnostic and prognostic information in patients with idiopathic dilated cardiomyopathy; however, the yield of useful information with this procedure among patients with heart failure is low, and the risks of occasional cardiac perforation and death further limit its use. Recent publications in the field of myocarditis and cardiomyopathy have renewed interest in the use of EMB in select patients to diagnose specific and potentially treatable myocarditides; however, the role of EMB in the work-up of patients with dilated cardiomyopathy is not well defined. In this article, we discuss the risks and utility of EMB in the management of patients with dilated cardiomyopathy and specific myocarditides. [References: 81]

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Unique Identifier:9628566

Authors: Hrobon P. Kuntz KM. Hare JM.

Institution: Harvard School of Public Health, Boston, Mass, USA.

Title: Should endomyocardial biopsy be performed for detection of myocarditis? A decision analytic approach.

Source: Journal of Heart & Lung Transplantation. 17(5):479-86, 1998 May.

Abstract: BACKGROUND: Performance of endomyocardial biopsy (EMB) to diagnose myocarditis in patients with dilated cardiomyopathy is controversial because of a lack of evidence favoring immunosuppressive therapy. In spite of advances in heart failure treatment, dilated cardiomyopathy carries a poor prognosis, and myocardial inflammation and viral infection are potential therapeutic targets. METHODS: We used decision analysis to determine the efficacy (5-year risk reduction in mortality or transplantation) that a treatment for myocarditis would require to favor a biopsy-guided approach over conventional therapy. Literature-based estimates included prevalence of myocarditis among patients with dilated cardiomyopathy with or without borderline myocarditis (16% and 11%, respectively); probability of 5-year transplantation-free survival (55%); sensitivity (50% and 63%, respectively), specificity (95.4%), and mortality rate (0.4%) of EMB; side effects resulting in withdrawal of immunosuppressive treatment (4%); and a 6-month mortality rate for immunosuppressive treatment (0.1%). All estimates were varied to determine impact on model results (sensitivity analysis). RESULTS: A therapy that decreased the rate of death or transplantation by 12.7% and 7.1% for patients without or with borderline myocarditis, respectively, favored EMB. Sensitivity analysis indicated that therapeutic efficacy was influenced by myocarditis prevalence and biopsy-related death, but not by accuracy of biopsy or probability of immunosuppressive therapy side effects. Randomized trials powered to detect 7% and 25% reductions in death and transplantation would require 5790 and 380 end points, respectively. CONCLUSION: Decreasing the rate of death or transplantation by 7.1% offsets therapy side effects, EMB-related death, and inaccuracies in histologic diagnosis. Prospective randomized trials of treatments for myocarditis may be more feasible during periods of high prevalence or with more sensitive diagnostic techniques. CAS Registry/EC Number 0 (Immunosuppressive Agents).