Myocarditis: Early Biopsy Allows for Tailored Regenerative Treatment
Background and methods
Myocarditis and inflammatory cardiomyopathies can be caused by infections, drugs, toxic substances, and autoimmune diseases. We present their clinical features, diagnostic evaluation, treatment, and prognosis on the basis of a selective review of the literature, current expert opinion, and our own clinical experience.
The pathological mechanisms that are accessible to treatment lie at the cellular and molecular levels and generally give rise to nonspecific disease manifestations. Specific treatment is possible only on the basis of a standardized diagnostic evaluation of a biopsy specimen, rather than clinical examination alone. Therapeutic decisions must be based on the results of thorough myocardial biopsy studies while taking account of the individual patient's clinical course. Moreover, treatment can help only if a treatable cause is present (e.g., a viral infection, an inflammatory process, or cardiodepressive antibodies), and only if the myocardium still has regenerative potential. Once irreversible myocardial injury has occurred-for example, if the diagnosis of post-infectious or post-inflammatory dilated cardiomyopathy has been missed until it is too late-then the development or progression of heart failure in the long term can no longer be prevented.
Recent studies have shown that specific treatment can help patients with viral, inflammatory, or autoimmune cardiomyopathy that has been precisely characterized by means of a myocardial biopsy. More randomized trials with larger patient cohorts are needed for further optimization of treatment.