Two-dimensional echocardiographic contrast studies were performed in 16 patients with pericardial effusion. A 4-chamber view was obtained by positioning the transducer at the apex. The exploratory needle was visualized in 9 patients. Five milliliters of saline solution were injected through the exploring needle and a cloud of echoes indicated its position. Microbubbles were seen in all 16 patients. This technique enabled the operator to identify that the needle was inadvertently in the left ventricle in 2 patients and in the right ventricle in 1. Furthermore, in 2 patients, when fluid could not be aspirated, the contrast study confirmed that the needle was in the pericardial sac; in both cases, pericardial fluid could be aspirated with slight manipulation of the needle. In a patient with a stab wound a negative contrast effect indicated the probable site of laceration. Thus, 2-dimensional contrast echocardiography was useful in locating needle position, which facilitated pericardiocentesis.