The presence of pericardial effusion always raises concern for cardiac tamponade. Echocardiographic signs of tamponade include right ventricular (RV) diastolic collapse, right atrial collapse during ventricular systole, reciprocal respiratory changes in RV and left ventricular filling, and dilation of the inferior vena cava (IVC). In the presented case, the RV diastolic volume appeared small, but diastolic RV collapse resulting from tamponade was not clearly seen; however, it may be difficult to appreciate the typical appearance of RV collapse in the presence of the large mass. If the intrapericardial pressure exceeds RV diastolic pressure, RV collapse and tamponade will ensue, but only if the RV free wall is normal in thickness and compliance. The large mass adherent to the RV possibly decreased the compliance of the RV free wall, preventing any increased pericardial pressure to be transmitted to the right ventricle. Right atrial collapse during ventricular systole has a very high sensitivity for tamponade, and its absence, as seen in Video 2, makes tamponade unlikely. A nondilated IVC with > 50% respiratory variation, as shown in Video 2, also argues against the presence of tamponade. IVC collapsibility carries a high negative predictive value for tamponade. Plethora of the IVC has a sensitivity of 97% but only 40% specificity.