The Parameters tab shows the results obtained for a processed gated study.
Parameter Table
The table lists the estimated functional metrics, namely
Ejection fraction (EF) |
▪Fraction of outbound blood pumped from the heart with each heartbeat, calculated as (EDV-ESV)/EDV. |
End Diastolic Volume, EDV (ED volume) |
▪Volume of the left ventricle at diastole. ▪Determined as the biggest volume of the endocardial contour in the cardiac cycle. ▪Is closely related to venous compliance. |
End Systolic Volume, ESV (ES volume) |
▪Volume of the left ventricle at the end of contraction. ▪Determined as the smallest ventricle volume of the endocardial contour in the cardiac cycle. |
Stroke Volume (SV) |
▪Blood volume pumped from the left ventricle of the heart per beat, calculated as EDV-ESV. |
Stroke Index (SI) |
▪Stroke volume (SV) in relation to the body surface area (BSA), calculated as SV/BSA. NOTE: SI is provided only if the patient height and weight are available, otherwise it is NaN. Note that these fields can be edited. |
Myocardial Mass (MM) |
▪Approximated by multiplying the difference of the epi- and endocardial volumes by the density of the myocardial tissue (1.04 g/cm3). |
Peak Filling Rate (PFR) |
▪Most rapid change in the ventricular volume, usually occurring in the initial period of fast filling. ▪Is defined as the maximal value of the first derivative of the time-volume curve. |
Time to Peak Fill Rate (TPFR) |
▪Interval in milliseconds between the time of minimal ventricular volume (ESV) and the time of the determined peak filling rate (PFR). |
1/3 filling rate |
▪Filling rate from the time of minimal ventricular volume (ESV) to 1/3 of the total filling time. |
1/3 filling fraction |
▪Fraction of volume filled until 1/3 filling time. |
LV Time-Volume Curve
In the plot section the volume of left ventricle is shown as a function of time in the heart cycle. To inspect the curve in a larger window, click with the right mouse button into the curve area and select View in Separate Window from the context menu. The example below shows a typical time-volume curve.
A time-volume curve is expected to have its minimum (end-systole) at gate3 or 4, and its maximum (end-diastole) at frame 1 or 8 in gated acquisitions with 8 frames. Major deviations from this behavior indicate a gating failure, and the acquisition should be repeated.
Polar Plots
The polar plots show either the tracer uptake at the End Systole or End Diastole, or the percent Wall Thickening. An overlay showing 3 vascular territories (Arterial), 4 Sectors or 20 segments (20 AHA sectors) can be selected from the pull-down menu to right of the overlay toggle 
.
By default, Arterial definition is used. The + button allows using an explicitly defined maximum rather than the maximum in the data, which can be specified in the adjacent number field. The numbers in the polar plot overlay represent the average value in the territory or sector. When the cursor is moved about a polar plot the instantaneous value is shown in the upper right. The polar plot display control can be switched on/off by right clicking into the polar plot area and selecting the Hide/Show Controls option. After enabling the controls, the thresholds of the color table can be interactively adjusted. With the Properties entry in the context menu, display properties like Description's font size can be changed.