ECG trigger-delay was accurately set to mid-diastolic "motion freezing" by observing the movement profile of RCA cross-points on four-chamber view individually.

Remember that you need to press a letter key or keys to trigger the rocket motion; depending on your computer's speed, you might experience a slight delay before the rockets appear.

If the delta is ever negative, consider that an error, as you should never get an item from the queue with an earlier trigger time, when the delay has ended.