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Salvador Borges-Neto

Publications and source records attributed to Salvador Borges-Neto.

21 records · Page 2Linked to original sources

Gated 99mTc-tetrofosmin and 18F-FDG studies: a comparison of single-acquisition and separate-acquisition protocols.

UNLABELLED: 18F-FDG is a well-established tracer for evaluating myocardial viability, as is (99m)Tc-tetrofosmin (TET) for evaluating myocardial perfusion. Dual-isotope single-acquisition (DISA) studies using a (99m)Tc perfusion agent and (18)F-FDG have been performed to evaluate myocardial viability. The purpose of this investigation was to determine whether there is a difference in the results of gated SPECT DISA, compared with gated SPECT DIDA (dual-isotope dual-acquisition) studies using (99m)Tc-TET/(18)F-FDG and a high-energy collimated dual-head SPECT system. METHODS: We prospectively studied 13 patients with depressed left ventricular function using both acquisition protocols. Summed rest scores were calculated for both (99m)Tc and (18)F-FDG studies using a 12-segment model and a 5-grade severity score. Images were evaluated by a single reader who did not know whether the images were acquired separately or simultaneously. RESULTS: The concordance of DISA and DIDA protocols for (99m)Tc-TET when allowing no difference in the SRS was 57%, or 89 of 156 segments. The concordance of DISA and DIDA protocols for (18)F-FDG was 86%, or 134 of 156 segments. The concordance of segments determined to be viable versus nonviable was 92%, or 143 of 156 segments. Ejection fraction measurements obtained by gated (99m)Tc-TET studies correlated strongly with those obtained by gated (18)F-FDG studies. CONCLUSION: A high concordance for (18)F-FDG studies was shown between gated DISA and gated DIDA. A lower concordance was shown between gated DISA and gated DIDA studies using (99m)Tc-TET, most likely because of downscatter from (18)F into the (99m)Tc window. An excellent concordance was demonstrated between the 2 techniques for viability assessment. The gated (99m)Tc-TET/(18)F-FDG DISA protocol can be both a reliable and an efficient way to evaluate myocardial function, perfusion, and viability.

Fluorodeoxyglucose F18↗

Clinical characteristics and referral pattern of patients with left ventricular dysfunction and significant coronary artery disease undergoing radionuclide imaging.

BACKGROUND: Many observational studies that predict patient outcomes have examined the use of myocardial perfusion imaging results. However, a referral pattern for radionuclide testing could bias these analyses and should be determined. These patients may also differ with regard to the extent of coronary artery disease (CAD). All of these differences must be incorporated into proper outcomes examinations. We sought to identify the nuclear perfusion imaging referral pattern for patients with left ventricular (LV) dysfunction and significant CAD. METHODS AND RESULTS: Patients with LV dysfunction and CAD (n = 2951) meeting our inclusion criteria were compared by receipt or absence of radionuclide perfusion testing within 6 months before or after angiography. Pearson chi2 and Kruskal-Wallis analyses were used to examine differences in baseline characteristics and catheterization results, whereas logistic regression modeling was applied to predict nuclear imaging referral before and after catheterization. Precatheterization nuclear cohort patients were more likely to be minority patients (odds ratio [OR], 1.34; P =.0083) with previous cardiac revascularization (OR, 2.27; P =.0001), Charlson comorbidity index greater than 1 (OR, 1.146; P =.0091), and heart failure symptoms (OR, 1.62; P =.0001) than those without imaging. They were less likely to have a myocardial infarction (OR, 0.464; P =.0001). After catheterization, the nuclear patients were more likely to have had congestive heart failure (OR, 1.452; P =.0019), a myocardial infarction (OR, 1.353; P =.0371), an ejection fraction lower than 30% (OR, 1.058; P =.0002), and prior revascularization (OR, 1.880; P =.0001). In addition, they had fewer diseased vessels (OR, 0.731; P =.0001). CONCLUSIONS: Bias exists in nuclear referral for patients with LV dysfunction and significant CAD and must be considered when interpreting observational studies on this topic.

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