ECG edition in dual source CT
The following question has been sent by Sofiane Hadjadj, MD, clinical research, Canada:
hi, we have just aquired the dual source ct, and I am very impressed by the quality of images for coro ct even with high calccium scoring, my question is regarding the EKG editing, are their any rules regarding this process for arythmias, which complex has to be deleted, which phase is the best for short rr, etc….
thank in advance for your help.
Martin Heuschmid, M.D., Associate Professor, University Hospital Tuebingen:
In short RR Intervalls you have to move more towards the systole, just like when the heart rate is elevated. In arrhythmias switching from the percentages to the fixed time settings post trigger (in the ECG pulsing chart upper left corner – i think, there is a drop down menu that lets you change between % and ms) may help. Otherwise you can choose a high frequency in the pulsing windows (go to ‘manual’ and choose the frequency range instead of leaving it at ‘auto’) to widen your pulsing window or just let the computer work its magic. We found that the pulsing algorhythm is very good at reacting to high frequencies and arrhythmias (its better when the patient is more arrhythmic, and kind of goes over the edge with a patient that only shows an extrasystole or two), it automatically widens the window and adjust to the heart beat. The only thing that will happen with arrhythmic patients the computer will send a lot of pop up windows telling you he will adapt the scan anew as the frequency has changed during the last ten beats, but you can just ignore this messages, you don’t even have to close the pop up window, as soon as you start scanning it will dissapear. For reconstruction try to distibute your reconstruction bars as evenly as possible and always in the same location to the RR cycle, so kick out the faster ones, but not more than 2,5s gaps or your image quality won’t work out.
See another answer to this question by Dr. Juergens
See another answer to this question by Dr. Achenbach
