During this step, you must identify end-diastole. This is the timepoint in the cardiac cycle when the volume of the LV blood pool is at its maximum. You can move through the different timepoints of the cardiac cycle by using the film strip shown at the bottom of the window. The film strip shows a row of boxes that each represent a frame of the current cine. You can click and drag across these boxes in order to switch between frames. The selected image is displayed in the main pane of the window and the corresponding box in the timeline is highlighted in yellow. End-diastole can be identified by finding the frame of a mid-ventricular cine in which the cross sectional area of the LV blood pool is at its maximum. Usually, end-diastole is either the first or the last frame in the cardiac cycle.
Note - To allow you to click and drag in a smooth transition between the start and finish of the cine, the timeline provides a graphical representation of two cardiac cycles placed side-by-side. The selected frame is highlighted in both of the cardiac cycles. The illustration below shows the structure of the timeline. Notice the small vertical line that marks the division between the two cycles.
When examining the images, you can adjust their brightness and contrast by using the contrast slider to the right of the window. You can click and drag on the top of the slider to choose which image intensity value is represented by white, on the bottom of the slider to choose which value is represented by black, or in the middle of the bar to alter both of these values at the same time.
It is best to identify end-diastole on a mid-ventricular slice. This reduces errors that can be introduced by the apex and base of the ventricle contracting at different points in the cardiac cycle. To select a mid-ventricular slice, click and drag on the slice selector which is displayed in the top right corner of the image pane.
In order to start or stop the animation of the cine, click on the ‘play’ button to the left of the timeline.
In order to examine the images in more detail, click and drag on the magnify icon illustrated below. This will magnify the image, keeping the view centred on the left ventricle.
Once you have identified and selected an image in the end-diastolic phase, click on the next section of the workflow. You should now identify end-systole. This is the timepoint in the cardiac cycle when the volume of the LV is at its minimum. End-diastole can be identified by finding the frame of a mid-ventricular cine in which the cross sectional area of the LV blood pool is at its minimum. Once you have finished, click on the next section of the workflow.
Step 2 - Identifying phases
VentricularTools