We have performed 20 echocardiography-guided endomyocardial biopsies in 16 patients, totalling 98 bioptic samples. In each case fluoroscopy was available to supplement the echocardiographic findings. The right ventricle was biopsied in 17 cases, the left ventricle in 3. All 3 left ventricular biopsies and 14 out of 17 right ventricular biopsies were satisfactorily guided by echocardiography. An adequate echocardiographic window was not obtained in 3 cases of right ventricular biopsies and the procedures were carried out under fluoroscopy. In 5 cases (25%), totalling 10 samples, echocardiography showed a somewhat different position of the bioptome from that suggested by fluoroscopy, thus guiding a significant repositioning of it. Finally, in one patient, echocardiography promptly visualized a severe pericardial effusion, due to cardiac perforation, thus allowing its immediate drainage.