This new article by Cademartiri et al in the March 2006 issue of the AJR, talks about how you can edit the ECG trace to take care of rhythm abnormalities. Though I may be wrong, apparently this is a feature available only on Siemens scanners and is an extremely powerful tool.
The next three entries starting with this one show how ECG-editing is an integral part of our cardiac CT examination. We have been able to take care of extrasystoles, bigeminies, regularly irregular rhythms and other unusual rhythm abnormalities with adequately diagnostic images. In fact the general rule is to scan the patients anyway and then work on the ECG trace. It is a rare patient where we haven't been able to generate diagnostic quality images.
This patient was a 65-years old man who in the latter half of the study landed up with a ventricular tachycardia-like situation with the heart rate jumping to more than 150 with irregularity (Figs. 1A, 1B). At 40%, which was the best reconstruction phase, the study was completely non-diagnostic (Figs. 2A, 2B). Subsequently, we edited the ECG (Figs. 3A, 3B) and obtained a perfectly diagnostic dataset at 40% (Figs. 4A, 4B). 
This feature, is not available only on Siemens. We work in Brazil with Philips and we use a lot is very helpfull and we don't need to call back the patient.
Posted by: Marcelo Hadlich | March 10, 2006 at 07:59 AM
We use a Philips 64 slice scanner and it too has the ability to edit the cardiac rhythm prior to reconstructing the data.
Thank you for your excellent web site. I have gone there many times.
Yours,
Roy Gottlieb, D.O.
Posted by: Roy Gottlieb | March 11, 2006 at 10:24 PM