Abstract
Intrapericardial and right auricular pressures were measured in a patient who had hemorrhagic pericardial effusion due to carcinomatous invasion of the pericardium. The auricular pressure was measured by a catheter passed up the left antecubital vein with the tip located in the auricle by x-ray. Cardiac output was normal before and after pericardial aspiration, with fall in intrapericardial and right auricular pressures, though the filling pressure of the right auricle (difference between right auricular and intrapericardial pressures) was normal both times. Increase of venous pressure provides the filling pressure for the auricles in cardiac tamponade, and cardiac output is not impaired; this will obtain until intrapericardial pressure reaches the venous pressure, after which the cardiac output will fall.