To investigate the relationship between age-related blood flow velocity and heart rate in the left ventricular inflow tract, we studied 118 healthy volunteers (age > 15 years). The maximal velocity (Vmax) of the transmitral diastolic flow during FIGURE 1. Illustration of a cross section of the left
Phasic flow in the left ventricular inflow tract: The importance of Doppler sample volume position
โ Scribed by Ben J. Delemarre; Hans Bot; Cees A. Visser; Arend J. Dunning
- Publisher
- John Wiley and Sons
- Year
- 1988
- Tongue
- English
- Weight
- 539 KB
- Volume
- 16
- Category
- Article
- ISSN
- 0091-2751
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โฆ Synopsis
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.
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