Evaluation of the Role of Endomyocardial Biopsy in Rare Myocardial Disorders: Six Case Reports and Narratives

This study conducts an observational analysis of 6 cases of rare myocardial diseases, aiming to clarify the diagnostic value and clinical utility of endomyocardial biopsy (EMB) in the 2007 American Heart Association, American College of Cardiology, and European Society of Cardiology guidelines and the 2020 Heart Failure Association of the European Society of Cardiology, Heart Failure Society of America, and Japanese Heart Failure Society guidelines. Our findings indicated that certain forms of myocarditis may present with arrhythmias and other clinical scenarios, potentially leading to a lower recommendation grade in the 2007 guidelines. To enhance the yield of EMB, electroanatomical mapping systems can be used in some diseases. Endomyocardial biopsy serves as a valuable diagnostic tool in acute-onset unexplained cardiomyopathy and suspected infiltrative diseases. The complications of EMB must be taken seriously.