Survey of Aorta and Coronary Arteries With Prospective ECG-Triggered 100-kV 64-MDCT Angiography
June 25th, 2009 Posted by: admin
OBJECTIVE. The purpose of this study was to investigate the
feasibility of prospective ECG-triggered axial 64-MDCT angiography of the
aorta and coronary arteries performed at a tube voltage of 100 kV.
SUBJECTS AND METHODS. Thirty patients with a heart rate less than 75
beats/min who were referred for aortic CT angiography were enrolled. The image
quality of the ascending aorta, aortic valve, and coronary arteries was
evaluated for motion artifacts. Contrast enhancement (mean attenuation) was
measured in the ascending aorta, descending aorta, and bifurcation of the
aorta. Aortic valve and coronary artery lesions were surveyed.
RESULTS. Acceptable image quality was achieved in 100% (30/30) of
cases for the ascending aorta, 97% (29/30) of cases for the aortic valve, and
98% (442/452) of coronary arterial segments. Contrast enhancement was greater
than 200 HU and was satisfactory (ascending aorta, 379 ± 80 HU;
descending aorta, 354 ± 72 HU; bifurcation, 355 ± 96 HU).
Lesions found in the aortic valve were plaque (n = 16) and bicuspid
valve (n = 1) and in the coronary arteries were ≥ 50% luminal
stenosis (n = 5), plaque (n = 21), myocardial bridge
(n = 12), and anomalous origin (n = 1). The effective
radiation dose was estimated to be 7.5 ± 1.7 mSv.
CONCLUSION. For patients with a heart rate less than 75 beats/min,
prospective ECG-triggered axial CT angiography at a tube voltage of 100 kV has
the potential to provide clinically relevant information about the aorta and
coronary arteries with low radiation exposure.
