title: Influence of Pulsed-Doppler Sample Volume Location and Upper Body Tilt on Left Ventricular Filling Indices in Healthy Persons.
abstract: Doppler echocardiographic analysis of mitral flow is a noninvasive tool for analyzing left ventricular diastolic function. Changes in preload alter both normal and abnormal Doppler patterns of left ventricular filling. The velocities of mitral flow measured by transthoracic pulsed-Doppler echocardiography are different when measured at the mitral leaflet tips and at the mitral annulus. Transesophageal echocardiography provides an excellent image of cardiac anatomy whereby it is possible to place the Doppler sample volume exactly at the mitral annulus or at the tips of mitral leaflets. We studied with the use of transesophageal echocardiography how changes in preload and measurement at the annulus or valve tips affect the velocities of mitral flow. Upper body-up tilting (60 degrees ) decreased maximum E wave velocity by 16% and, hence, E/A ratio by 15%. A wave did not change by tilt. E wave velocity was 13%-15% lower at the annulus than at the tips of the mitral valve in both the supine and tilt position. E/A ratio was significantly higher at the tips than at the annulus of the mitral valve (supine, P = 0.048; tilt, P = 0.001). E/A ratio was 38% lower if the measurements were done at the annulus in the tilt position than at the tips with the patient lying horizontal. It may be important for pulsed-Doppler mitral flow-velocity measurements to be standardized for sample volume location and for body position.
authors.affiliation: Department of Medicine, Tampere University Hospital, P.O. Box 2000, FIN-33521 Tampere, Finland.
authors.forename: Vesa
authors.lastname: Virtanen
authors.forename: Kaj
authors.initials: K
authors.lastname: Groundstroem