Combined non-invasive CT coronary angiography (CTA) and myocardial perfusion (CTP) with 320-detector row CT allows accurate identification of flow-limiting lesions requiring revascularisation, according to results from the CORE320 study, a worldwide multicentre trial assessing the diagnostic performance of combined CTA and CTP as compared to traditional assessment of flow-limiting stenosis by means of SPECT-MPI and invasive coronary angiography (ICA).
Results of the trial, sponsored by Toshiba Medical Systems Corporation, were presented by João A C Lima, senior author of the study and professor of Medicine and Radiology at the Johns Hopkins University School of Medicine, during an ESC 2012 Hotline Session.
“The CORE 320 study is the first prospective, multicentre study to examine the diagnostic accuracy of CT for assessing blockages in blood vessels and determining which of those blockages may be preventing the heart from getting adequate blood flow. We found an excellent correlation in results when we compared the 320-detector CT testing with the traditional means of assessment using a stress test with imaging and cardiac catheterisation” said Lima.
Three hundred and eighty one patients completed all imaging and were included in the primary analysis. The patient-based diagnostic accuracy (AUC) of combined CTA and CTP for detecting or excluding flow-limiting coronary arterial disease (CAD) without history of CAD was 0.93 when the ICA stenosis reference standard was ≥50%. CTP increased the diagnostic accuracy of CTA alone to delineate flow-limiting disease (AUC: 0.87 vs. 0.81 respectively, p<0.001). The combination of CTA and CTP had similar diagnostic power to the combination of ICA and SPECT-MPI in identifying revascularised patients at 30 days.
The researchers say the two tests combined CTA and CTP still produce less radiation than a cardiac scan with the 64-slice CT scanner in widespread use today. Lima said “In our study, the amount of radiation exposure to patients from the two 320 slice CT scanner tests was half the amount they received as a result of the traditional evaluation methods the angiogram and nuclear medicine stress test combined”.
Aquilion ONE (Toshiba) was the CT system used in CORE320, according to Toshiba, its ability to capture the entire heart in a single temporally uniform volume permits accurate myocardial perfusion analysis. The perfusion technique developed for Aquilion ONE provides perfusion images at the lowest possible radiation dose when AIDR 3D, iterative reconstruction, is applied. “CORE320 has shown that it is now possible to perform a comprehensive cardiac functional and morphological analysis in just one, low-dose examination using Aquilion ONE. This technology can reduce the need to perform multiple examinations using different modalities, a true economical advantage and valuable contribution in cardiac healthcare” said Satoshi Tsunakawa, president of Toshiba Medical Systems Corporation.