Ruling out Coronary Artery Disease with 0.69 mSv

Ralf W. Bauer, MD, J. Matthias Kerl, MD and Thomas J. Vogl, MD
Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Frankfurt/Germany
 |  2010-04-28


A 68-year-old patient with atypical chest pain and known year-long arterial hypertension presented at our department in order to rule out coronary artery disease. Ultrasound showed concentric LV hypertrophy and aortic valve stenosis grade 1. Resting heart rate was 50 bpm and no beta-blockers were injected.


Coronary CT angiography using the prospectively ECG-gated Flash Spiral was performed utilizing only 0.69 mSv radiation dose. We found mild concentric LV hypertrophy and minor calcifications of the aortic valve. There was no sign of macroangiopathic arteriosclerotic changes in the main coronary arteries and their major branches. Coronary artery disease could be ruled out in this patient.


Coronary CT angiography using 100 kV tube potential and the Flash Spiral acquisition mode allowed ruling out coronary artery disease in this normal-sized adult patient (185 cm/ 86 kg) with a DLP of 49 in only 0.29 seconds scan time without the use of beta blockers. The smallest myocardial branches of the RCA, LAD and LCX could be visualized underlining best image quality at lowest dose values.

Examination Protocol

Scanner SOMATOM Definition Flash
Scan area Heart
Scan length 135 mm
Scan direction Cranio -Caudal
Scan time 0.29 sec
Tube voltage 100 kV / 100 kV
Tube current 370 mAs/rot
Dose modulation CARE Dose 4D
CTDIvol 2.59 mGy
DLP 49 mGy/cm
Effective Dose 0.69 mSv
Rotation time 0.28 s
Pitch 3.4
Slice collimation 128 x 0.6 mm
Slice width 0.75 mm
Spatial Resolution 0.33 mm
Reconstruction increment 0.4 mm
Reconstruction kernel B26f
Volume 70 ml contrast
Flow rate 5 ml/s
Start delay Test bolus

The information presented in this case study is for illustration only and is not intended to be relied upon by the reader for instruction as to the practice of medicine. Any health care practitioner reading this information is reminded that they must use their own learning, training and expertise in dealing with their individual patients. This material does not substitute for that duty and is not intended by Siemens Medical Systems to be used for any purpose in that regard.

The drugs and doses mentioned herein are consistent with the approval labeling for uses and/or indications of the drug. The treating physician bears the sole responsibility for the diagnosis and treatment of patients, including drugs and doses prescribed in connection with such use. The Operating Instructions must always be strictly followed when operating the CT System. The source for the technical data is the corresponding data sheets. Results may vary.