The User Interface for 30-second and 60-second long 1 lead telemetry strips is shown below. The interface consists of two defined regions.

1. The top region, the Analysis Window, is the region you will use to interact with the ECG using calipers.
2. The bottom region, the Navigation Window, is the region you will use to move around the entire strip and zoom in and out on the ECG.

The Navigation Window provides a low-resolution view of the entire telemetry strip, offering an overview of its contents. The pink box in the Navigation Window is called the Navigation Box. The Navigation Box serves three purposes:

1. Display Control: Defines the region of the telemetry strip shown in the Analysis Window, allowing you to navigate across the strip.
2. Zooming: Enables zooming in and out of the ECG.
3. Movement: Facilitates easy navigation across the entire telemetry strip.

To zoom in or out, position the mouse cursor on an edge of the Navigation Box. The cursor will change to either , indicating you can resize the Navigation Box horizontally, or , indicating that you can resize the Navigation Box vertically.

• Horizontal resizing: Adjust the width of the Navigation Box by dragging left or right.
• Vertical resizing: Adjust the height of the Navigation Box by dragging up or down.

Once the cursor changes, press and hold the mouse button, then drag in the desired direction to resize the Navigation Box. As you resize, the ECG in the Analysis Window will adjust accordingly, becoming larger or smaller. Figure 2 illustrates this process, showing how resizing zooms in on the ECG.

To move the Navigation Box, position the mouse cursor inside it. The cursor will change will change to , indicating movement is possible. Press and hold the left mouse button, then drag the Navigation Box to the desired location.

As you move the Navigation Box, the Analysis Window updates to display the corresponding region of the ECG. Figure 3 demonstrates this process, moving the Navigation Box to the right.

The Analysis Window displays the ECG in greater detail, allowing for precise measurements. You can use calipers in this window to measure intervals and amplitudes on the ECG. Two caliper modes are available:

• Time Caliper: For measuring time intervals.
• Voltage Caliper: For measuring amplitudes.

The active caliper mode is displayed in the lower-right corner of the Analysis Window, as shown in the inset figure to the right.

To activate the Time Caliper, press the 'T' key while the mouse is in the Analysis Window. When activated:

1. The Caliper Mode indicator in the lower-right corner updates.
2. The cursor changes to a caliper, as shown in Figure 4.

Press the 'T' key again to deactivate the Timing Caliper.

To create a Time Caliper, follow these steps:

1. Move the left arm of the caliper cursor to the desired start location.
2. Press and hold the left mouse button, then drag the mouse left or right to begin measuring.
3. As you move the mouse, the Time Caliper Measurement comprising two lines and a measurement box will appear on the ECG.
4. Release the mouse button at the desired end location to finalize the measurement.

To measure a different region of the ECG when a Time Caliper Measurement is already present, repeat the steps outlined above but start the measurement outside the boundaries of the existing one.

To adjust the start or stop locations of an existing Time Caliper Measurement, follow these steps:

1. Place the mouse cursor over one of the two measurement lines. The cursor will change to , indicating the line can be moved.
2. Press and hold the left mouse button, then drag the line left or right to the desired position.
3. Release the mouse button to set the new location.

Alternatively, you can adjust the caliper using the keyboard.

You can reposition a Time Caliper Measurement within the Analysis Window. For example, to compare the RR intervals between different QRS complexes:

1. Place the mouse cursor between the two measurement lines. The cursor will change to , indicating the measurement can be moved.
2. Click and hold the left mouse button, then drag the measurement to the desired location.
3. Release the mouse button to set the new position.

Alternatively, you can move the Time Caliper using the keyboard.

To clear a Time Caliper Measurement, you can

1. Click the mouse on the ECG in the Analysis Window outside of the Time Caliper Measurement
2. Toggle the caliper mode off and then on again by pressing the 'T' key twice
3. Pressing the 'Escape' key

The Voltage Caliper mode is activated by pressing the 'V' key while the mouse is in the Analysis Window. When you press the 'V' key, notice that the Caliper Mode indicator in the lower right corner of the Analysis Window updates, and the cursor in the Analysis Window changes to a caliper, as you see in the following image. Pressing the 'V' key again will turn off the Timing Caliper.

To use the Voltage Caliper, move the top arm of the caliper cursor to the desired start location. Press and hold the left mouse button and move the mouse up or down to begin measuring. A Voltage Caliper Measurement consisting of two caliper lines and a measurement box will appear on the ECG as you move the mouse. When you reach the desired end location, release the left mouse button. The Voltage Caliper Measurement will remain on the ECG.

If a Voltage Caliper Measurement is present on the ECG and you want to measure a different region, repeat the steps for creating a measurement region with a starting position outside the current Voltage Caliper Measurement.

After creating a Voltage Caliper Measurement, you can adjust the start and stop locations by moving the measurement lines. Place the mouse cursor over one of the measurement lines. The mouse cursor will change to , indicating the measurement location can be changed. Then press and hold the left mouse button and move the mouse up or down to set a new location. When at the desired new location, release the left mouse button. The updated Voltage Caliper Measurement will remain on the ECG. You can adjust the Voltage Caliper using the keyboard.

You can move a Voltage Caliper Measurement around the ECG in the Analysis Window to check for consistent voltage measurements across the ECG. First, place the mouse cursor between the two measurement lines to move the Voltage Caliper Measurement. The mouse cursor will change to to indicate you can move the measurement. Then click and hold the left mouse button and then move the mouse up or down to the desired new location. You can also move the Voltage Caliper using the keyboard.

To clear a Voltage Caliper Measurement, you can

1. Click the mouse on the ECG in the Analysis Window outside of Voltage Caliper Measurement
2. Toggle the caliper mode off and then on again by pressing the 'V' key twice
3. Pressing the 'Escape' key