Endomyocardial biopsy in the USA

Summary

The rather widespread adoption of endomyocardial biopsy in the USA has occurred mainly due to newer and safer techniques and the need to study more completely an increasingly prevalent population of patients presenting with idiopathic myocardial disease. Investigators caution, however, that without firmer knowledge the technique of biopsy may be limited to detection of allograft rejection, grading of anthracycline toxicity, and uncovering of occasional, very rare myocardial conditions, a few of which are treatable. Myocarditis, in particular, is the subject of much interest and at the same time, much controversy. Many feel that myocarditis is quite common, but figures show that incidence varies greatly depending upon pathologic interpretation. For this reason, a consensus opinion as to diagnostic histopathologic criteria is being generated by expert workers in the field. In addition, several workers are attempting to develop broader and deeper probes into ways in which biopsy tissue may be used. These include immunochemical staining, enzymatic and biochemical measurements, quantitative techniques using electron microscopy, and the in vitro use of biopsy-obtained myocardium for studies in mechanical function, beta-adrenergic receptor profiles, and immunologic reactions. Further development of instruments continues. This includes the use of a special sheath to allow sampling from the right ventricular septal endomyocardium from femoral vein access. Also, a disposable bioptome assembly is now marketed. The original Stanford-developed internal jugular approach remains the most well-known and widely practiced technique.