Randomized comparison of 64-slice single- and dual-source computed tomography coronary angiography for the detection of coronary artery disease.
OBJECTIVE
The purpose of this study was to analyze the influence of a systematic approach to lower heart rate for coronary computed tomography (CT) angiography on diagnostic accuracy of 64-slice single- and dual-source CT.


BACKGROUND
Coronary CT angiography is often impaired by motion artifacts, so that routine lowering of heart rate is usually recommended. This is often conceived as a major limitation of the technique. It is expected that higher temporal resolution, such as with dual-source 64-slice CT, would allow diagnostic imaging even without systematic pre-treatment for lowering the heart rate.


METHODS
Two hundred patients with suspected coronary artery disease were first randomized to either 64-slice single-source CT (n = 100) or dual-source CT (n = 100) for contrast-enhanced coronary artery evaluation. In each group, patients were further randomized to either receive systematic heart rate control (oral and intravenous beta-blockade for a target heart rate < or =60 beats/min) or receive no premedication. Evaluability of datasets and diagnostic accuracy were compared between groups against the results obtained from invasive angiography.


RESULTS
Systematic pre-treatment lowered heart rate during CT coronary angiography by 10 beats/min. Heart rate control significantly improved evaluability in single-source CT (93% vs. 69% on a per-patient basis, p = 0.005), whereas it did not in dual-source CT (96% vs. 98%). In evaluable patients, sensitivity to detect the presence of at least 1 coronary stenosis by single-source CT was 86% and 79%, respectively, with and without heart rate control (p = NS). For dual-source CT, it was 100% and 95%, respectively (p = NS). The rate of correctly classified patients, defined as evaluable and correct classification as to the presence or absence of at least 1 coronary artery stenosis, was significantly improved by heart rate control in single-source CT (78% vs. 57%, p = 0.04), whereas there was no such influence in dual-source CT (87% vs. 93%).


CONCLUSIONS
Systematic heart rate control significantly improves image quality for coronary visualization by 64-slice single-source CT, whereas image quality and diagnostic accuracy remain unaffected in dual-source CT angiography. Improved temporal resolution obviates the need for heart rate control.
Department of Cardiology, University of Erlangen, Germany. Stephan.achenbach@ukerlangen.de
Stephan
S
Achenbach
Ulrike
U
Ropers
Axel
A
Kuettner
Katharina
K
Anders
Tobias
T
Pflederer
Sei
S
Komatsu
Werner
W
Bautz
Werner G
WG
Daniel
Dieter
D
Ropers
D000284:Administration, Oral; D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage*; D000368:Aged; D017023:Coronary Angiography / Q000295:instrumentation / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004867:Equipment Design; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011856:Radiographic Image Enhancement; D011857:Radiographic Image Interpretation, Computer-Assisted; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed / Q000295:instrumentation
D000319:Adrenergic beta-Antagonists