UNUSUAL HEMODYNAMIC FINDINGS OF DIAGNOSTIC VALUE IN A CASE OF LEFT ATRIAL MYXOMA

Unusual laboratory findings in a case of left atrial myxoma are presented. The end-diastolic pressure gradient between the left ventricle and wedge position ranged from 0 to 21 mm. Hg with no relation to heart rate or rhythm, respiration, or wedge position. The y descent was slow rather than the usual rapid y descent associated with mobile atrial myxomas. These findings probably were caused by left atrial inflow obstruction rather than outflow obstruction. Pressure transients owing to sudden acceleration and deceleration of the tumor and surrounding blood, with subsequent oscillations of the heart and great vessels, were recorded in the left ventricle, aorta, external carotid pulse, and external phonocardiogram during the phase of isovolumic contraction and during a period beginning with isovolumic relaxation through rapid ventricular filling. These findings, when present, strongly suggest the presence of a mobile atrial tumor. © 1969.