Viewpoints in the diagnosis and treatment of cardiac sarcoidosis: Proposed modification of current guidelines

Isolated cardiac sarcoidosis is a generally accepted disease condition, and the low yield of endomyocardial biopsy because of patchy involvement is also well known. However, current guidelines still require histologic confirmation of granuloma for the diagnosis of cardiac sarcoidosis, either in myocardial or extra-cardiac tissues. Therefore, only a presumptive diagnosis of chronic multifocal myocarditis of unknown origin can be made in a large number of patients in whom the only considerable diagnosis is cardiac sarcoidosis based on current knowledge. Even if these patients are treated with the same treatment scheme as that for cardiac sarcoidosis, which may not cause harm in the absence of a definite diagnosis, the true spectrum of cardiac sarcoidosis could not be determined for deciding the optimal treatment strategy. In addition, the current recommendations for dose, duration of initial steroid therapy, and treatment in patients who did not respond to initial steroid therapy are not easy to follow in real-world practice. We would like to propose a scoring system for the diagnosis of cardiac sarcoidosis and suggest our adoption or modification of the diverse current recommendations.