Objective: To compare prospective electrocardiogram (ECG)-triggered high-voltage coronary computed tomography (CT) angiography (CTA; 140-kVp P-cCTA) with retrospective ECG-gated standard-voltage cCTA (120-kVp R-cCTA), in patients with coronary stents.
Methods: Fifty-two patients with coronary stents were studied with 64-slice multidetector scanner. Ninety-three stents were analyzed: 55 with 140-kVp P-cCTA and 38 with 120-kVp R-cCTA. Image quality (IQ), diagnostic confidence (DC), in-stent assessable lumen, artificial narrowing, and effective radiation dose were compared between techniques.
Results: Image quality and DC were significantly better for the 140-kVp P-cCTA in comparison with the 120-kVp R-cCTA (IQ, 1.1 ± 0.36 vs 1.7 ± 0.60, respectively; P < 0.00001. Diagnostic confidence: 1.1 ± 0.29 vs 1.5 ± 0.65 respectively; P < 0.0001). In-stent assessable lumen and artificial narrowing were comparable between the techniques. Effective dose was lower for the 140-kVp P-cCTA (6.7 ± 2.07 mSv vs 15.8 ± 6.89 mSv; P < 0.0001).
Conclusions: High voltage combined with axial prospective ECG-triggered scan improved IQ and DC in stent cCTA imaging but failed to improve the diameter of in-stent assessable lumen and to reduce the artificial narrowing compared with the 120-kVp R-cCTA. Effective dose was 60% lower for the 140-kVp P-cCTA.
From the *Department of Radiology and Experimental Imaging Center, San Raffaele Scientific Institute and Vita-Salute University; and †Medical Physics Service, San Raffaele Scientific Institute, Milan, Italy.
Received for publication October 20, 2012; accepted January 10, 2013.
Reprints: Antonio Esposito, MD, Department of Radiology and Experimental Imaging Center, San Raffaele Scientific Institute and Vita-Salute San Raffaele University, Via Olgettina 60, 20132, Milan, Italy (e-mail: email@example.com).
The authors have no conflict of interest to report.