Talal Asif1, Javier Gomez1,2, Vasvi Singh3,4,5, Rami Doukky1,2, Arlet Nedeltcheva1, Saurabh Malhotra6,7,8. 1. Division of Cardiology, Cook County Health, Chicago, USA. 2. Division of Cardiology, Rush Medical College, Chicago, USA. 3. Division of Cardiovascular Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, USA. 4. Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Brigham and Women's Hospital, Boston, MA, USA. 5. Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA. 6. Division of Cardiology, Cook County Health, Chicago, USA. saurabh.malhotra@cookcountyhhs.org. 7. Division of Cardiology, Rush Medical College, Chicago, USA. saurabh.malhotra@cookcountyhhs.org. 8. Division of Cardiovascular Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, USA. saurabh.malhotra@cookcountyhhs.org.
Abstract
BACKGROUND: Tc-99m pyrophosphate (PYP) SPECT is recommended for indeterminate findings on planar imaging. We aimed to compare the findings on planar PYP scintigraphy alone to that of routinely performed PYP SPECT. METHODS: PYP scintigraphy data of 133 patients (53% men; mean age 76 years) were evaluated. SPECT was routinely performed following 1-hour planar imaging, in all cases. Semiquantitative visual score and heart-to-contralateral (H/CL) ratio were determined in all patients as recommended. RESULTS: PYP images from 35 patients (26%) were considered to be positive based on SPECT myocardial uptake. Among them, 20 (57%) had a H/CL ratio ≥1.5 and 34 had a visual score ≥ 2. SPECT identified myocardial uptake in one patient with a visual score < 2 and refuted the presence of myocardial uptake in two patients with a visual score ≥ 2. Visual score correlated well with SPECT (r = 0.94; P < .0001) and had an accuracy of 98% for tomographic myocardial uptake. Addition of H/CL ratio reduced the diagnostic performance of visual score. CONCLUSIONS: Planar-derived visual score has an excellent accuracy for tomographic myocardial uptake, though it misclassifies a small proportion of patients. H/CL ratio decreases the diagnostic certainty of planar imaging. Tomographic imaging prevents misdiagnoses and should always be performed.
BACKGROUND: Tc-99m pyrophosphate (PYP) SPECT is recommended for indeterminate findings on planar imaging. We aimed to compare the findings on planar PYP scintigraphy alone to that of routinely performed PYP SPECT. METHODS: PYP scintigraphy data of 133 patients (53% men; mean age 76 years) were evaluated. SPECT was routinely performed following 1-hour planar imaging, in all cases. Semiquantitative visual score and heart-to-contralateral (H/CL) ratio were determined in all patients as recommended. RESULTS: PYP images from 35 patients (26%) were considered to be positive based on SPECT myocardial uptake. Among them, 20 (57%) had a H/CL ratio ≥1.5 and 34 had a visual score ≥ 2. SPECT identified myocardial uptake in one patient with a visual score < 2 and refuted the presence of myocardial uptake in two patients with a visual score ≥ 2. Visual score correlated well with SPECT (r = 0.94; P < .0001) and had an accuracy of 98% for tomographic myocardial uptake. Addition of H/CL ratio reduced the diagnostic performance of visual score. CONCLUSIONS: Planar-derived visual score has an excellent accuracy for tomographic myocardial uptake, though it misclassifies a small proportion of patients. H/CL ratio decreases the diagnostic certainty of planar imaging. Tomographic imaging prevents misdiagnoses and should always be performed.
Authors: Weijia Li; Dipan Uppal; Yu-Chiang Wang; Xiaobo Xu; Damianos G Kokkinidis; Mark I Travin; James M Tauras Journal: Diagnostics (Basel) Date: 2021-05-30