Evaluation of patients with coronary artery disease

Summary

Quantification of myocardial perfusion scintigraphy is often performed to assist physicians in detecting coronary artery disease (CAD). Modern software and hardware packages provide improvements able to shorten scan time and/or reduce administered activity, without compromising image quality in radionuclide myocardial perfusion imaging (MPI). Recently, multifocal collimators were introduced with dedicated reconstruction software, named IQ-SPECT, able to shorten considerably scan time. The aim of our study was to compare this new protocol to the already validated standard ones. Patients, methods: We enrolled 43 patients with suspected or diagnosed CAD. All patients underwent a two-days protocol radionuclide myocardial perfusion scan at rest and after a standard stress test (exercise or dipyridamole) after administering ^99mTc-tetrofosmin. Images were acquired on a 2-head gamma camera and reconstructed with attenuation correction. All the images were scored using a 17-segments model by three experienced physicians, blind to clinical data and to acquisition and processing modality. Results, conclusion: No significant differences were recorded in perfusion scores on paired t-test and Wilcoxon among the full-time images reconstructed with standard protocol or IQSPECT, both overall on a 17-segments evaluation and when considering different territories of distribution. MPI with IQ-SPECT protocol can be acquired at about a quarter scan time without disagreement compared to full time scan acquisition performed with standard protocols.

Zusammenfassung

Häufig werden myokardiale Perfusionsszintigraphien quantifiziert, um den Arzt bei der Diagnose der koronaren Herzkrankheit (KHK) zu unterstützen. Moderne Hard- und Software bietet Verbesserungen, die verkürzte Aufnahmezeiten und/oder geringere Strahlenbelastungen ermöglichen ohne die Bildqualität der myokardialen Perfusionsszintigraphie (MPS) zu beeinträchtigen. Kürzlich wurden multifokale Kollimatoren mit Rekonstruktionssoftware, genannt IQ-SPECT, eingeführt, womit die Scanzeit erheblich verkürzt werden kann. In unserer Studie sollte dieses neue Protokoll mit dem bereits validierten Standardvorgehen verglichen werden. Patienten, Methoden: Eingeschlossen wurden 43 Patienten mit vermuteter oder diagnostizierter KHK. Sie wurden einem zweitägigen Protokoll mit Radionuklid- Myokard-Perfusionsscan in Ruhe und nach standardisiertem Belastungstest (Ergometrie oder Dipyridamol) nach Gabe von ^99mTc-Tetrofosmin unterzogen. Die Aufnahmen mit einer Doppelkopf-Gammakamera wurden mittels Abschwächungskorrektur rekonstruiert. Alle Aufnahmen wurden von drei erfahrenen Ärzten, die bezüglich der klinischen Angaben sowie der Aufnahme- und Verarbeitungsmodalitäten verblindet waren, anhand eines 17-Segment-Modells ausgewertet. Ergebnisse, Schlussfolgerung: Im t-Test für verbundene Stichproben und Wilcoxon- Test wurden keine wesentlichen Unterschiede bei den Perfusionswerten zwischen den Vollzeit-Aufnahmen mit Standardprotokoll und IQ-SPECT festgestellt, sowohl insgesamt in der 17-Segment-Auswertung als auch unter Berücksichtigung verschiedener Verteilungsgebiete. Die MPS mit einem IQ-SPECT-Protokoll kann ohne Abweichungen in etwa einem Viertel der Scanzeit akquiriert werden, die für die Aufnahmen in Vollzeit mit dem Standardprotokoll benötigt wird.

Keywords

Coronary artery disease - ^99mTc tetrofosmin SPECT/CT - IQ-SPECT - low counts acquisition - myocardial perfusion imaging

Schlüsselwörter

Koronare Herzkrankheit - ^99mTc-Tetrofosmin SPECT/CT - IQ-SPECT - Erfassung niedriger Counts - Myokard-Perfusions-aufnahmen

• References

• 1 Ali I, Ruddy TD, Almgrahi A. et al. Half-time SPECT myocardial perfusion imaging with attenuation correction. J Nucl Med 2009; 50: 554-562.
• 2 Berman DS, Hachamovitch R, Shaw LJ. et al. Roles of nuclear cardiology, cardiac computed tomography, and cardiac magnetic resonance: assessment of patients with suspected coronary artery disease. J Nucl Med 2006; 47: 74-82.
• 3 Bossuyt PM, Reitsma JB, Bruns DE. et al. Towards complete and accurate reporting of studies of diagnostic accuracy: the STARD initiative. Br Med J 2003; 326: 41-44.
• 4 Buechel RR, Herzog BA, Husmann L. et al. Ultrafast nuclear myocardial perfusion imaging on a new gamma camera with semiconductor detector technique: first clinical validation. Eur J Nucl Med Mol Imaging 2010; 37: 773-778.
• 5 Caldwell JH, Williams DL, Harp GD. et al. Quantitation of size of relative myocardial perfusion defect by single-photon emission computed tomography. Circulation 1984; 70: 1048-1056.
• 6 Daou D, Pointurier I, Coaguila C. et al. Performance of OSEM and depth-dependent resolution recovery algorithms for the evaluation of global left ventricular function in 201Tl gated myocardial perfusion SPECT. J Nucl Med 2003; 44: 155-162.
• 7 DePuey G, Bommireddipalli S, Clark J. et al. Wide beam reconstruction “quarter-time” gated myocardial perfusion SPECT functional imaging: a comparison to “full-time” ordered subset expectation maximum. J Nucl Cardiol 2009; 16: 736-752.
• 8 DePuey G, Gadiraju R, Anstett F. et al. Half-time gated myocardial perfusion SPECT processed with both OSEM with resolution recovery and wide beam reconstruction: clinical performance compared to full-time filtered backprojection. In: Proceedings of the ICNC meeting. May 2 2007. Prague, Czech Republic: Abstract 472.
• 9 Einstein AJ, Moser KW, ThompIon RC. et al. Radiation dose to patients from cardiac diagnostic imaging. Circulation 2007; 116: 1290-1305.
• 10 Hansen CL, Akinboboye OO, Berman DS. et al. Myocardial perfusion and function Single Photon Emission Computed Tomography. J Nucl Cardiol 2007; 14: e39-60e41.
• 11 Irwig L, Tosteson ANA, Gatsonis C. et al. Guidelines for meta-analyses evaluating diagnostic tests. Ann Intern Med 1994; 120: 667-676.
• 12 Kapur A, Latus KA, Davies G. et al. A comparison of three radionuclide myocardial perfusion tracers in clinical practice: the ROBUST study. Eur J Nucl Med Mol Imaging 2002; 29: 1608-1616.
• 13 Kritzman JN, Cahill JM, Ficaro EP, Corbett JR. Quantitative comparison of standard and reduced acquisition time attenuation corrected and noncorrected myocardial perfusion images: a phantom study utilizing a 3D iterative reconstruction [abstract]. J Nucl Cardiol 2007; 14 (Suppl. 01) S107-S108.
• 14 Maddahi J, Mendez R, Mahmarian JJ. et al. Prospective multicenter evaluation of rapid, gated SPECT myocardial perfusion upright imaging. J Nucl Cardiol 2009; 16: 351-357.
• 15 Matsumoto N, Berman DS, Kavanagh PB. et al. Quantitative assessment of motion artifacts and validation of a new motion-correction program for myocardial perfusion SPECT. J Nucl Med 2001; 42: 687-694.
• 16 Rajaram R, Bhattacharya M, Ding X. et al. Tomographic performance charachteristics of the IQSPECT system. IEEE Nuclear Science Symposium Conference Record 2011
• 17 Slomka PJ, Berman DS, Germano G. Applications and software techniques for integrated cardiac multimodality imaging. Expert Rev Cardiovasc Ther 2008; 6: 27-41.
• 18 Tsui BMW, Hu HB, Gilland DR, Gullberg GT. Implementation of simultaneous attenuation and detector response correction in SPECT. IEEE Trans Nucl Sci 1988; 35: 778-783.
• 19 Underwood SR, Anagnostopoulos C, Cerqueira M. et al. Myocardial perfusion scintigraphy: the evidence. Eur J Nucl Med Mol Imaging 2004; 31: 261-291.
• 20 Venero CV, Heller GV, Bateman TM. et al. A multicenter evaluation of a new post-processing method with depth-dependent collimator resolution applied to full-time and half-time acquisitions without and with simultaneously acquired attenuation correction. J Nucl Cardiol 2009; 16: 714-725.
• 21 Vija H, Malmin R, Yahil A. et al. A method for improving the efficiency of myocardial perfusion imaging using conventional SPECT and SPECT/CT imaging systems. IEEE Nuclear Science Symposium and Medical Imaging Conference Record 2010
• 22 White CW, Wright CB, Doty DB. et al. Does visual interpretation of the coronary arteriogram predict the physiologic importance of a coronary stenosis?. N Engl J Med 1984; 310: 819-824.