Improved diagnostic accuracy of planar imaging with technetium 99m-labeled tetrofosmin compared with thallium-201 for the detection of coronary artery disease.

BACKGROUND

Receiver operating characteristic (ROC) curve analysis provides detailed information about the performance of a diagnostic test.

METHODS AND RESULTS

As part of a multicenter phase III trial, 160 patients with known or suspected coronary artery disease underwent planar stress-rest 99mTc-labeled tetrofosmin and stress-redistribution 201Tl imaging within 14 days of each other, to compare the diagnostic accuracy of these imaging modalities by ROC curve analysis. Coronary arteriography was used as the reference standard and greater than 70% stenosis was considered significant. ROC curve analysis showed improved detection of coronary artery disease with 99mTc-labeled tetrofosmin compared with 201Tl, with ROC curve areas of 0.765 versus 0.644, respectively (p = 0.02). 99mTc-labeled tetrofosmin also better identified single-vessel disease in those without previous myocardial infarction (ROC curve areas of 0.684 vs 0.510 for 99mTc-labeled tetrofosmin and 201Tl, respectively; p = 0.04) and enhanced the detection of multivessel disease in those with previous myocardial infarction (ROC curve areas of 0.764 vs 0.638, respectively; p = 0.02).

CONCLUSIONS

Detailed assessment of diagnostic performance by ROC curve analysis shows that, for planar imaging, 99mTc-labeled tetrofosmin enhances the detection of coronary artery disease compared with 201Tl.