Quantitative assessment of myocardial perfusion abnormality on SPECT myocardial perfusion imaging is more reproducible than expert visual analysis

• Authors: Daniel S. Berman, University of California Los Angeles; Xingping Kang, Cedars Sinai Heart Institute; Heidi Gransar, Cedars Sinai Heart Institute; James Gerlach, Cedars Sinai Heart Institute; John D. Friedman, University of California Los Angeles; Sean W. Hayes, University of California Los Angeles; Louise E. J. Thomson, Cedars Sinai Heart Institute; Rory Hachamovitch, Private Practice; Leslee J Shaw, Emory University; Piotr J. Slomka, University of California Los Angeles; Ling De Yang, Cedars Sinai Heart Institute; Guido Germano, University of California Los Angeles
• Proceedings Title: Journal of Nuclear Cardiology
• Conference Name: 55th Annual Meeting of the Society-of-Nuclear-Medicine
• Publisher: Springer
• Conference Place: New Orleans, LA
• Volume/Issue: Volume 16 | Issue 1
• Publication Date: 2009-02-01
• Type of Work: Conference | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1007/s12350-008-9018-0
• Subjects: Health Sciences, Medicine and Surgery
• Keywords: Science & Technology; Life Sciences & Biomedicine; Cardiac & Cardiovascular Systems; Radiology, Nuclear Medicine & Medical Imaging; Cardiovascular System & Cardiology; Myocardial perfusion SPECT; quantification; reproducibility; CORONARY-ARTERY-DISEASE; EMISSION COMPUTED-TOMOGRAPHY; TRANSIENT ISCHEMIC DILATION; MEDICAL THERAPY; QUANTIFICATION; TRIAL; REVASCULARIZATION; INTERVENTION; INFARCTION; OUTCOMES

Abstract

Background: Current guidelines of Food and Drug Administration for the evaluation of SPECT myocardial perfusion imaging (MPI) in clinical trials recommend independent visual interpretation by multiple experts. Few studies have addressed whether quantitative SPECT MPI assessment would be more reproducible for this application. Methods and Results: We studied 31 patients (age 68 ± 13, 25 male) with abnormal stress MPI who underwent repeat exercise (n = 11) or adenosine (n = 20) MPI within 9-22 months (mean 14.9 ± 3.8 months) and had no interval revascularization or myocardial infarction and no change in symptoms, stress type, rest or stress ECG, or clinical response to stress on the second study. Visual interpretation per FDA Guidance used 17-segment, 5-point scoring by two independent expert readers with overread of discordance by a third expert, and percent myocardium abnormal was derived from normalized summed scores. The quantitative magnitude of perfusion abnormality was assessed by the total perfusion deficit (TPD), expressing stress, rest, and ischemic perfusion abnormality. High linear correlations were observed between visual and quantitative size of stress, rest, and ischemic defects (R = 0.94, 0.92, 0.84). Correlations of two tests were higher by quantitative than by visual methods for stress (R = 0.97 vs R = 0.91, P = 0.03) and rest defects (R = 0.94 vs R = 0.82, P = 0.03), respectively, and statistically similar for ischemic defects (R = 0.84 vs R = 0.70, P = ns). Conclusions: In stable patients having serial SPECT MPI, quantification is more reproducible than visual for magnitude of perfusion abnormality, suggesting its superiority for use in randomized clinical trials and monitoring the effects of therapy in an individual patient.