Phasic flow in the left ventricular inflow tract: the importance of Doppler sample volume position.
Variability of Doppler transmitral flow was studied in 42 normal patients (aged 19-68 years). Starting at the mitral annulus level (ANL) in an apical four-chamber view, the sample volume was moved downstream at 1-cm intervals. At all positions, peak early (E) and later atrial mediated (A) diastolic velocity were measured, and the distance from the transducer to the level with the highest E wave (HEL) and highest A wave (HAL) determined. The A/E ratio and time velocity integral (TVI) at ANL, HAL, and HEL were also calculated. Peak E velocity at HEL was 33% higher than at ANL (p less than 0.01) and peak A velocity was 15% higher at HAL than at ANL (p less than 0.01). The A/E ratio was minimal at HEL and maximal at ANL (0.68 +/- 0.28 vs 0.85 +/- 0.32, p less than 0.01), whereas TVI was highest at HEL and lowest at ANL. Thus, inflow parameters vary along the inflow axis. This is of importance for cardiac output measurement. The A/E ratio was more dependent on age than on sample volume position.
Delemarre
B J
BJ
Department of Cardiology, Academic Medical Center, Amsterdam, The Netherlands.
Bot
H
H
Visser
C A
CA
Dunning
A J
AJ
D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology; D002302:Cardiac Output / Q000502:physiology*; D003971:Diastole / Q000502:physiology*; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000502:physiology; D009200:Myocardial Contraction / Q000502:physiology*; D012044:Regression Analysis; D016276:Ventricular Function