CMR versus SPECT for diagnosis of coronary heart disease/Authors' reply

[...]stress perfusion CMR alone has already been compared with FFR and shown to have an even better diagnostic accuracy than that reported by Greenwood and colleagues (positive predictive value 90.9%, negative predictive value 93.9%).2 Similar findings were reported by Rieber and colleagues,5 again using CMR perfusion imaging alone. The state-of-theart technology is applied only for CMR imaging. [...]SPECT shows incon clusive results, mainly because of patient motion or attenuation artefacts secondary to long acquisition times and lack of attenuation correction, which are in great part solved by use of modern SPECT instrumentation.3,4 Additionally, by contrast with CMR assess ment, criteria for a positive SPECT are not detailed, which might explain the low diagnostic accuracy reported for SPECT (eg, how is ischaemia assessed?).