In the intensive care unit, cardiac tamponade may occur following cardiac surgery, traumatic injury, pericardial effusion, or as a result of myocardial infarction with wall rupture. Rarely, tamponade may occur as a complication of central venous line placement or other procedures. Clinically, cardiac tamponade may present with Beck's triad of hypotension, elevated jugular venous pressure, and muffled heart sounds. However, the absence of these symptoms does not exclude the diagnosis of tamponade, as lesser volumes or chronic accumulation may present with more subtle clinical findings. TEE is highly sensitive and specific in the detection of pericardial tamponade, with accuracy greater than 99%.9 Pericardial fluid can often be detected in the TG midpapillary SAX, TG LAX, and ME four-chamber views (Figure 22–1). Restriction of cardiac filling and equalization of pressures between the left and right heart may manifest via flattening of the interventricular septum, decreased left ventricular end-diastolic volume, decreased LV size during inspiration, and diastolic posterior motion of the RV.