A comparison of three radionuclide myocardial perfusion tracers in clinical practice: the ROBUST study

Abstract

There are technical differences between the tracers. Overall image quality score is superior using technetium, with less low-count artefact and less attenuation. Stress defect depth and extent are slightly greater using thallium, with no difference between MIBI and tetrofosmin. All three tracers perform well in clinical terms, with high sensitivity and specificity for angiographic stenosis and no differences in accuracy between the tracers.

Impact of ACE and ApoE polymorphisms on myocardial perfusion: correlation with myocardial single photon emission computed tomographic imaging

“…12 For SPECT interpretation, the myocardium of the left ventricle was divided into 17 segments, according to previous reports. 20,21 Two independent experienced observers blindly evaluated the reconstructed images, the polar maps and the three-dimensional images of both stress and rest studies by scoring the radiotracer uptake in each of the 17 regions, using a 5-point scoring system (0: normal uptake; 1: mildly reduced uptake; 2: moderately reduced uptake; 3: severely reduced uptake and 4: no uptake). 20,21 In 12 studies (5.8%) in which discordance between the two observers was detected (difference 42 in SSS and/or SRS values), the view of a third observer was requested and the disagreement was resolved by consensus.…”

“…20,21 Two independent experienced observers blindly evaluated the reconstructed images, the polar maps and the three-dimensional images of both stress and rest studies by scoring the radiotracer uptake in each of the 17 regions, using a 5-point scoring system (0: normal uptake; 1: mildly reduced uptake; 2: moderately reduced uptake; 3: severely reduced uptake and 4: no uptake). 20,21 In 12 studies (5.8%) in which discordance between the two observers was detected (difference 42 in SSS and/or SRS values), the view of a third observer was requested and the disagreement was resolved by consensus. 13,19,20 Ischemia was considered in every region of the myocardium with an uptake higher than 0 at stress imaging and a reduction of the score by, at least, one unit at rest.…”

“…20,21 In 12 studies (5.8%) in which discordance between the two observers was detected (difference 42 in SSS and/or SRS values), the view of a third observer was requested and the disagreement was resolved by consensus. 13,19,20 Ischemia was considered in every region of the myocardium with an uptake higher than 0 at stress imaging and a reduction of the score by, at least, one unit at rest. Finally, the 'summed stress score' (SSS) and 'summed rest score' (SRS) were obtained by adding the scores of the regions in stress and rest studies.…”

“…Subsequently, a 'summed difference score' (SDS) was estimated by subtracting the SRS from the SSS to assess defect reversibility. 13,[19][20][21] Studies with an SSS value equal or o2 were considered normal, an SSS value of 3-8 was considered mildly abnormal, a score of 9-13 moderately abnormal and an SSS413 was considered severely abnormal. 22 …”

Novel SPECT perfusion imaging agents with improved myocardial or liver kinetics: Experimental studies and the need for clinical evaluation

“…However, in addition to suboptimal myocardial extraction in comparison to that of Tl-201 due to the roll-off phenomenon leading to underestimation of myocardial perfusion at high flow rates, 7 Tc-MIBI also presents a modest heartto-liver activity ratio which is comparable or lower than that of Tl-201 and which might be responsible for misinterpretation of myocardial perfusion in the inferior or inferoapical left ventricular wall. 11,12 In the clinical setting however, despite these different biological, physical, and imaging characteristics, both Tl-201 and Tc-MIBI have comparable diagnostic accuracies for detecting coronary artery disease, as confirmed in the large randomized ROBUST study. 12 Similarly, the prognostic power of nuclear perfusion imaging-i.e., its ability for predicting future coronary events-has been demonstrated in a large number of high-quality studies and in thousands of patients, whatever the tracer used.…”