<div class="section">
<a class="named-anchor" id="ab-hoi170038-1">
<!--
named anchor
-->
</a>
<h5 class="section-title" id="d4403033e576">Importance</h5>
<p id="d4403033e578">At present, the choice of noninvasive testing for a diagnosis
of significant coronary
artery disease (CAD) is ambiguous, but nuclear myocardial perfusion imaging with single-photon
emission tomography (SPECT) or positron emission tomography (PET) and coronary computed
tomography angiography (CCTA) is predominantly used for this purpose. However, to
date, prospective head-to-head studies are lacking regarding the diagnostic accuracy
of these imaging modalities. Furthermore, the combination of anatomical and functional
assessments configuring a hybrid approach may yield improved accuracy.
</p>
</div><div class="section">
<a class="named-anchor" id="ab-hoi170038-2">
<!--
named anchor
-->
</a>
<h5 class="section-title" id="d4403033e581">Objectives</h5>
<p id="d4403033e583">To establish the diagnostic accuracy of CCTA, SPECT, and PET
and explore the incremental
value of hybrid imaging compared with fractional flow reserve.
</p>
</div><div class="section">
<a class="named-anchor" id="ab-hoi170038-3">
<!--
named anchor
-->
</a>
<h5 class="section-title" id="d4403033e586">Design, Setting, and Participants</h5>
<p id="d4403033e588">A prospective clinical study involving 208 patients with suspected
CAD who underwent
CCTA, technetium 99m/tetrofosmin–labeled SPECT, and [
<sup>15</sup>O]H
<sub>2</sub>O PET with examination of all coronary arteries by fractional flow reserve
was performed
from January 23, 2012, to October 25, 2014. Scans were interpreted by core laboratories
on an intention-to-diagnose basis. Hybrid images were generated in case of abnormal
noninvasive anatomical or functional test results.
</p>
</div><div class="section">
<a class="named-anchor" id="ab-hoi170038-4">
<!--
named anchor
-->
</a>
<h5 class="section-title" id="d4403033e597">Main Outcomes and Measures</h5>
<p id="d4403033e599">Hemodynamically significant stenosis in at least 1 coronary artery
as indicated by
a fractional flow reserve of 0.80 or less and relative diagnostic accuracy of SPECT,
PET, and CCTA in detecting hemodynamically significant CAD.
</p>
</div><div class="section">
<a class="named-anchor" id="ab-hoi170038-5">
<!--
named anchor
-->
</a>
<h5 class="section-title" id="d4403033e602">Results</h5>
<p id="d4403033e604">Of the 208 patients in the study (76 women and 132 men; mean
[SD] age, 58 [9] years),
92 (44.2%) had significant CAD (fractional flow reserve ≤0.80). Sensitivity was 90%
(95% CI, 82%-95%) for CCTA, 57% (95% CI, 46%-67%) for SPECT, and 87% (95% CI, 78%-93%)
for PET, whereas specificity was 60% (95% CI, 51%-69%) for CCTA, 94% (95% CI, 88%-98%)
for SPECT, and 84% (95% CI, 75%-89%) for PET. Single-photon emission tomography was
found to be noninferior to PET in terms of specificity (
<i>P</i> < .001) but not in terms of sensitivity (
<i>P</i> > .99) using the predefined absolute margin of 10%. Diagnostic accuracy
was highest
for PET (85%; 95% CI, 80%-90%) compared with that of CCTA (74%; 95% CI, 67%-79%;
<i>P</i> = .003) and SPECT (77%; 95% CI, 71%-83%;
<i>P</i> = .02). Diagnostic accuracy was not enhanced by either hybrid SPECT and CCTA
(76%;
95% CI, 70%-82%;
<i>P</i> = .75) or by PET and CCTA (84%; 95% CI, 79%-89%;
<i>P</i> = .82), but resulted in an increase in specificity (
<i>P</i> = .004) at the cost of a decrease in sensitivity (
<i>P</i> = .001).
</p>
</div><div class="section">
<a class="named-anchor" id="ab-hoi170038-6">
<!--
named anchor
-->
</a>
<h5 class="section-title" id="d4403033e632">Conclusions and Relevance</h5>
<p id="d4403033e634">This controlled clinical head-to-head comparative study revealed
PET to exhibit the
highest accuracy for diagnosis of myocardial ischemia. Furthermore, a combined anatomical
and functional assessment does not add incremental diagnostic value but guides clinical
decision-making in an unsalutary fashion.
</p>
</div><p class="first" id="d4403033e637">This head-to-head comparative study evaluates
the diagnostic accuracy of coronary
computed tomography angiography, single-photon emission tomography, and positron emission
tomography and explores the incremental value of hybrid imaging compared with fractional
flow reserve.
</p><div class="section">
<a class="named-anchor" id="ab-hoi170038-7">
<!--
named anchor
-->
</a>
<h5 class="section-title" id="d4403033e643">Question</h5>
<p id="d4403033e645">What are the diagnostic performances of coronary computed tomography
angiography,
single-photon emission tomography, [
<sup>15</sup>O]H
<sub>2</sub>O positron emission tomography, and hybrid imaging for the diagnosis of
myocardial
ischemia using fractional flow reserve as a reference standard?
</p>
</div><div class="section">
<a class="named-anchor" id="ab-hoi170038-8">
<!--
named anchor
-->
</a>
<h5 class="section-title" id="d4403033e654">Findings</h5>
<p id="d4403033e656">In this head-to-head comparative study of 208 adults, sensitivity
was 90% for coronary
computed tomography angiography, 57% for single-photon emission tomography, and 87%
for positron emission tomography, whereas specificity was 60% for coronary computed
tomography angiography, 94% for single-photon emission tomography, and 84% for positron
emission tomography. Positron emission tomography exhibited the highest diagnostic
accuracy compared with single-photon emission tomography and coronary computed tomography
angiography.
</p>
</div><div class="section">
<a class="named-anchor" id="ab-hoi170038-9">
<!--
named anchor
-->
</a>
<h5 class="section-title" id="d4403033e659">Meaning</h5>
<p id="d4403033e661">Coronary computed tomography angiography and [
<sup>15</sup>O]H
<sub>2</sub>O positron emission tomography are both useful in the diagnosis of myocardial
ischemia,
while single-photon emission tomography and hybrid imaging guide clinical decision
making in an unsalutary fashion.
</p>
</div>