Send to

Choose Destination
Int J Cardiol. 2013 Oct 3;168(3):2811-5. doi: 10.1016/j.ijcard.2013.03.066. Epub 2013 Apr 22.

Diagnostic accuracy of coronary 320 slice CT angiography using retrospective electrocardiogram gated acquisition compared with virtual prospective electrocardiogram gated acquisition with and without padding.

Author information

Department of Cardiovascular Medicine, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba 260-8670, Japan.



To reduce radiation-exposure, prospective-ECG-gating without padding is preferable. To evaluate diagnostic-accuracy of coronary 320-slice-CT angiography using various-acquisition-methods, we compared retrospective-ECG-gated with dose-modulation and "virtual" prospective-ECG-gating with and without padding.


We retrospectively selected seventy-seven consecutive symptomatic subjects (52-males, 62 ± 12 years) with normal-sinus-rhythm who underwent both retrospective-ECG-gated 320-slice-CT and conventional-coronary-angiograms (CCAG) within 3-months. CT images were reconstructed at 5% from 0 to 95% of RR-interval. Three-methods were used to assess >50% coronary-stenosis; 1) using only 75% of data named virtual prospective-ECG-gating without padding, 2) using 70-100% of data if heart-rate (HR) was <66 beats/minute (bpm), or using 35-100% of data if HR was >65 bpm, named as virtual prospective-ECG-gating with padding, and 3) using all-phase-data named retrospective-ECG-gating.


In 42-subjects with HR <66 bpm, there were zero unevaluable-segments in virtual prospective-ECG-gating with and without padding and retrospective-ECG-gating. But in 35-subjects with HR >65 bpm, the percentage of unevaluable-segments were significantly-higher in virtual prospective-ECG-gating without padding (13.6 ± 27.9%) than in virtual prospective-ECG-gating with padding (0.7 ± 3.1%), and retrospective-ECG-gating (0.7 ± 3.1%) (both P = 0.012). Using only evaluable-lesions, in 35-subjects with HR >65 bpm, sensitivity, specificity, positive-predictive-value and negative-predictive-value of CT for detecting >50% luminal-stenosis compared with CCAG were 82%, 94%, 60%, and 98%, respectively, for virtual prospective-ECG-gating without padding, 97%, 96%, 73%, and 100%, respectively, for virtual prospective-ECG-gating with padding, and 97%, 96%, 73%, and 100%, respectively, for retrospective-ECG-gating (all P = not-significant).


Virtual prospective-ECG gating at 75% of RR-interval without padding had significantly-more unevaluable-segments than virtual prospective-ECG-gating with padding and retrospective-ECG-gating only in subjects with HR >65 bpm.


Coronary 320-slice CT angiography; Diagnostic accuracy; Padding; Retrospective ECG-gating; Virtual prospective ECG-gating

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center