Original ArticleAccuracy of myocardial perfusion imaging in detecting multivessel coronary artery disease: A cardiac CZT study
Introduction
Ischemic heart disease (IHD) is believed to be associated with the presence of angiographically significant atherosclerotic coronary lesions. Nevertheless, despite the existence of a relationship between coronary artery disease (CAD) severity and the degree of myocardial perfusion impairment,1 myocardial ischemia may occur in the absence of obstructive epicardial coronary stenosis,2,3 still bearing a relevant prognostic impact.2
On the other hand, numerous reports have shown that the hemodynamic impact of a coronary lesion may be variable,4 suggesting that a combined evaluation of coronary anatomy and myocardial ischemic burden could more reliably guide patients’ management.5
Myocardial perfusion imaging (MPI) by single-photon emission computed-tomography (SPECT) is a reference standard for the non-invasive evaluation of regional myocardial ischemia, providing a reproducible measure of myocardial perfusion heterogeneity and ischemic burden.6 Nevertheless, despite its overall high sensitivity in detecting the presence of obstructive CAD, SPECT-MPI has been shown to have a sub-optimal accuracy in patients where a balanced impairment of myocardial perfusion might be present, such as in those with diffuse disease.7, 8, 9 Moreover, on a per-vessel basis, it has been frequently suggested that the diagnostic accuracy of MPI might be lower in the right coronary artery (RCA) and left circumflex (LCX) territories, due to imaging artifacts.10,11
The introduction of dedicated cardiac cameras equipped with stationary cadmium-zinc-telluride (CZT) detectors might help to overcome these technical limitations of standard SPECT imaging gamma cameras.12,13 The high spatial resolution and photon sensitivity of these devices,14 might allow a more accurate depiction of regional myocardial blood flow heterogeneity than standard cameras, leading to a better definition of the specific impact of a given coronary lesion in patients with diffuse CAD. Moreover, the better image quality that can be obtained with CZT cameras12 might improve the accuracy in detecting CAD in myocardial regions traditionally characterized by a higher prevalence of artifacts, such as RCA and LCX territories. Interestingly, while relatively small studies have suggested a high diagnostic power of CZT-MPI in detecting CAD,12,15 an evaluation of the diagnostic accuracy of this new technology in a large population of consecutive patients with suspected IHD who also had coronary angiography is still lacking. The purpose of this study was to evaluate the diagnostic accuracy of MPI performed with a dedicated CZT camera in symptomatic patients for the detection of presence and extent of CAD.
Section snippets
Patient Population
Between January 2010 and December 2015, 695 consecutive patients with chest pain and either intermediate probability of CAD (513 patients)5 or previously known CAD (182 patients) underwent MPI with a CZT camera followed by invasive or computed-tomography (CT) angiography. Specifically, 83 patients [all with normal EF and a summed stress score (SSS) <5] were studied with CT, while 612 patients underwent invasive coronary angiography, according to our previously reported routine clinical protocol
Characterization of the Study Population
As shown in Table 1, 528/695 (76%) patients were males with a mean age of 71 ± 11 years. On coronary angiography, 441/695 (63%) of the patients showed significant CAD, in one (28%), two (19%), and three (17%) vessels. Of those patients, 9/695 (1%) had a ≥50% left-main stem stenosis. The majority of patients (65%) underwent exercise stress testing, while 35% underwent vasodilator stress. The latter patients were older (74 ± 11 vs 70 ± 11, P < .001) and were more frequently females (30% vs 21%, P
Discussion
The present study, conducted in a large population of symptomatic patients, shows that MPI on a dedicated CZT camera has an excellent accuracy in detecting CAD, particularly in the case of multivessel disease (i.e., triple-vessel CAD). The diagnostic accuracy of CZT-MPI was unrelated to the location of the affected vessel, reliably quantifying the extent of CAD in the majority of patients.
Limitations
The consecutive nature of the enrolment prevented the selection of a homogeneous population of patients. However, considering the large number of patients studied, the present data represent a close picture of the actual population of subjects submitted to MPI. Since in patients with preserved LV systolic function, and limited stress-induced myocardial perfusion heterogeneity (12% of the population), coronary anatomy was evaluated only by CT coronary angiography, some coronary stenoses could
Conclusions
In patients with suspected IHD, MPI on a dedicated CZT camera offers a high accuracy in detecting the presence of CAD, independently from the location of the culprit coronary lesion. Specifically, in patients with multivessel CAD, CZT-MPI offers may individuate the extent of anatomically significant CAD in the majority of patients with a low false-negative rate.
New Knowledge Gained
The sub-optimal accuracy of MPI performed with traditional SPECT cameras in detecting multivessel CAD has been frequently reported. Present results suggest that, in symptomatic patients with suspected IHD, MPI using a dedicated cardiac camera equipped with CZT detectors has an excellent diagnostic accuracy in correctly detecting the presence and extent of CAD, including multivessel CAD, independently of the location of coronary stenoses.
Disclosure
Alessia Gimelli, Riccardo Liga, Valerio Duce, Annette Kusch, Alberto Clemente, and Paolo Marzullo have no conflict of interest or relationship with industries to disclose.
References (28)
Does coronary flow trump coronary anatomy?
JACC Cardiovasc Imaging.
(2009)- et al.
Accuracy of dipyridamole SPECT imaging in identifying individual coronary stenoses and multivessel disease in women versus men
J Nucl Cardiol.
(2000) - et al.
Accuracy of exercise stress technetium 99 m sestamibi SPECT imaging in the evaluation of the extent and location of coronary artery disease in patients with an earlier myocardial infarction
J Nucl Cardiol.
(2000) - et al.
Accuracy of dobutamine technetium 99m sestamibi SPECT imaging for the diagnosis of single-vessel coronary artery disease: Comparison with echocardiography
Am Heart J
(2000) - et al.
Dobutamine-atropine stress echocardiography and dipyridamole sestamibi scintigraphy for the detection of coronary artery disease: Limitations and concordance
J Am Coll Cardiol
(2000) - et al.
Identification of severe and extensive coronary artery disease by automatic measurement of transient ischemic dilation of the left ventricle in dual-isotope myocardial perfusion SPECT
J Am Coll Cardiol.
(1996) - et al.
Myocardial imaging with 99mTc-Tetrofosmin: Influence of post-stress acquisition time, regional radiotracer uptake, and wall motion abnormalities on the clinical result
J Nucl Cardiol.
(2010) - et al.
Relation between myocardial blood flow and the severity of coronary-artery stenosis
N Engl J Med
(1994) - et al.
Coronary microvascular dysfunction
N Engl J Med
(2007) - et al.
Structural abnormalities of the coronary arterial wall—in addition to luminal narrowing—affect myocardial blood flow reserve
J Nucl Med
(2011)
2013 ESC guidelines on the management of stable coronary artery disease: The Task Force on the management of stable coronary artery disease of the European Society of Cardiology
Eur Heart J
EANM/ESC procedural guidelines for myocardial perfusion imaging in nuclear cardiology
Eur J Nucl Med Mol Imaging
Determination of extent and location of coronary artery disease in patients without prior myocardial infarction by thallium-201 tomography with pharmacologic stress
J Nucl Med
Comparison between ultrafast and standard single-photon emission CT in patients with coronary artery disease: A pilot study
Circ Cardiovasc Imaging.
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Alessia Gimelli and Riccardo Liga share the first co-authorship.
See related editorial, doi:10.1007/s12350-016-0432-4.