User's Manual

Acclarix LX3 Series Diagnostic Ultrasound System User Manual Measurements and Reports
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8.1.3.7. PG(Pressure Gradient)
PGmax and PGmean can be measured in Cardiac exams. The measurement method is manual trace.
Please refer to the steps of manual trace method in section 8.1.3.2 trace measurement for details.
8.1.3.8. Tei Index
The Tei index measurement is useful for the assessment of ventricular systolic and diastolic function.
Higher Tei index indicates decreased ventricular function.
To use the TEI measurement:
1. In Cardiac exams, invoke the generic measurement function on a Doppler strip.
2. Select Tei Index.
3. Measure COT (Mitral Valve Close-Open Duration ) by caliper pairs.
4. Measure ET (Ventricular Ejection Time) by caliper pairs.
5. The system calculates the Tei index automatically. The illustration is shown below:
8.1.3.9. dp/dt
The left ventricular dp/dt measurement is a useful index for evaluating myocardial contractility.
To use the dp/dt measurement:
1. In Cardiac exams, invoke the generic measurement function on a Doppler strip.
2. Select dp/dt.
3. Move the caliper to the position at the 100 cm/s scale on one of the cardiac cycles and press
the <Set> key.
4. Move the caliper to the position at 300 cm/s scale on the same cardiac cycle and press the
<Set> key. The time difference "
dt " between the two positions come out .
5. The system calculates dp/dt based on the
"dt " value . Formula:
dp/dt = 32/dt (mmHg/s)