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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 29, No 1, January/February 2018
AFRICA
21
available software requires manual correction near branch vessels.
Further refinements to the software are expected to reduce the
time burden and facilitate applications in daily practice.
Fourth, we did not measure the TAG cut-off value in our
study; we considered that a TAG cut-off value of –15.1 HU/10
mm, as previously described, would be significant.
7
This value
could have been influenced by the use of iodine contrast material,
the CT protocol, or TAG calculation method. However, the
value of –15.1 HU/10 mm is generally accepted, and therefore
our data do not conflict with the results of other studies.
Conclusion
This study found that the TAG of stress CCTA using a wide-
area detector CT yielded a high diagnostic performance as
well as high sensitivity and specificity for the detection of
haemodynamically significant coronary artery stenosis when
compared with stress perfusion CMR. We believe that the
addition of TAG to CCTA could allow for comprehensive
anatomical and functional assessments of CAD, but this remains
to be proven in appropriately designed prospective trials.
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