ABSTRACT
Endomyocardial biopsy has been used to establish a diagnosis in patients with myocardial dysfunction for over 40 years. The first procedures were performed to detect the presence of inflammation or specific pathologic findings associated with systemic diseases.1-4 With the advent of heart transplantation, endomyocardial biopsy became an essential tool in the diagnosis of allograft rejection. Specialized catheters and techniques were developed to allow the procedures to be performed efficiently at minimal risk.5-12 Endomyocardial biopsy procedures in infants and children offered additional challenges, and techniques were modified to accommodate smaller heart sizes and vessels.13-18
The indications for endomyocardial biopsy in adults and children have evolved over the years. In a recently published scientific statement sponsored by the American Heart Association, American College of Cardiology, and the European Society of Cardiology, the incremental diagnostic, prognostic, and therapeutic value of endomyocardial biopsy was estimated and compared with procedural risks in 14 clinical scenarios.19 The clinical scenarios most relevant to the pediatric age range and designated as class I and class IIa recommendations are summarized in Table 41.1. In addition to these scenarios, endomyocardial biopsy was classified as reasonable in the presence of heart failure and left ventricular dilation with new ventricular arrhythmias or heart block if cardiac sarcoidosis or idiopathic granulomatous myocarditis was suspected, or in patients with eosinophilia and a suspicion of hypersensitivity cardiomyopathy. The use of endomyocardial biopsy to evaluate the patient with a dilated left ventricle and unexplained chronic heart failure, heart failure with unexplained hypertrophic cardiomyopathy, suspected arrhythmogenic cardiomyopathy, and unexplained ventricular arrhythmias is controversial and, in most cases, these scenarios are not considered indications for endomyocardial biopsy in children.
