Comparison of echocardiography-guided and fluoroscopy-guided endomyocardial biopsy techniques

The accuracy of bioptome placement for endomyocardial biopsy was evaluated using standard fluoroscopic guidance and compared simultaneously with two-dimensional echocardiography in six healthy subadult grizzly bears (Ursus arctos horribilis). Despite perceived adequate positioning of the bioptome toward the septum when judged using fluoroscopy, only one out of the six placements were actually positioned in the right ventricular apex toward the septum when evaluated using two-dimensional echocardiography. The bioptome was readily relocated to the right ventricular apex/septal location by echocardiography. The forceps were easily visualized at all times and the open cups were readily directed into the desired location for biopsy. Based on a subjective score for tissue quantity from 1 to 4 (poor to excellent), biopsies collected by echocardiographic-guided technique had a mean score of 3.4, while biopsies collected by fluoroscopic-guided technique had a mean score of 1.8. In summary, this study suggests that endomyocardial biopsy locations can be accurately positioned using two-dimensional echocardiography with the advantages of less radiation, lower procedural costs, and direct visuatization of the sampling site. Clear definition of endocardial surface as afforded by echocardiography may enhance tissue sample quality and lower potential complications from this procedure.