Acute Pulmonary Edema in the Absence of Left Ventricular Failure

Abstract
Two patients have been observed to develop acute repetitive pulmonary edema in the absence of left ventricular failure as evidenced by a normal or near normal left atrial pressure recorded during these periods. Continuous monitoring of the left atrial pressure was made possible by a catheter inserted during open-heart surgery. Both patients suffered brain damage, presumably secondary to cerebral air embolism, and eventually succumbed. Although the authors think that a causal relationship between cerebral damage and pulmonary edema best explains the mechanism in these two patients, this must remain conjectural. Neurogenic pulmonary edema, however, has been assumed to be secondary to elevated left atrial and left ventricular end-diastolic pressures. If a specific relation exists in these patients, the findings herein described strongly suggest that this may not be the mechanism.