Dual-step prospective ECG-triggered 128-slice DSCT for evaluation of coronary arteries and cardiac function without heart rate control: a technical note

Purpose
To describe prospective ECG-triggered dual-source CT dual-step pulsing (pECG(dual_step)) for evaluation of coronary arteries and cardiac function.

Methods
Fifty-one consecutive patients pre- or post-cardiovascular surgery were examined with adaptive sequential tube current modulated (pECG(dual-step)) 128-slice dual-source CT without heart rate control (main padding window: 40 % RR interval > 65 bpm/70 % RR interval < 65 bpm). Image quality of coronary arteries was graded (4-point scale), and cardiac function was evaluated.

Results
Mean HR was 68 bpm. Thirty-seven patients were in stable sinus rhythm (SR); 14 had arrhythmia. Image quality of coronary arteries was diagnostic in 804/816 (98 %) of segments. The number of non-diagnostic segments was higher in patients with arrhythmia as compared to those in SR (4 % vs. 0.5 %; p = 0.01), and there were fewer segments with excellent image quality (79 % vs. 94 %; p < 0.001) and more segments with impaired image quality (p < 0.001 and p = 0.002). Global and regional LV function could be evaluated in 41 (80 %) and 47 (92 %) patients, and valvular function in 48 (94 %). In 11/14 of patients with arrhythmia, the second step switched to full mAs, increasing radiation exposure to 8.6 mAs (p < 0.001). The average radiation dose was 3.8 mSv (range, 1.7-7.9) in patients in SR.

Conclusion
pECG(dual-step)128-slice DSCT is feasible for the evaluation of coronary arteries and cardiac function without heart rate control in patients in stable sinus rhythm at a low radiation dose.

Authors: Feuchtner G, Götti R, Plass A, Baumueller S, Stolzmann P, Scheffel H, Wieser M, Marincek B, Alkadhi H, Leschka S.

Full text available: Eur Radiol. 2010 Apr 21. [Epub ahead of print]