These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Cardiac stress-rest single-photon emission computed tomography with technetium 99m-labeled tetrofosmin: influence of washout kinetics on regional myocardial uptake values of the rest study with a 1-day protocol. Author: Schulz G, Ostwald E, Kaiser HJ, vom Dahl J, Kleinhans E, Buell U. Journal: J Nucl Cardiol; 1997; 4(4):298-301. PubMed ID: 9278876. Abstract: BACKGROUND: The purpose of this study was to evaluate (1) the washout kinetics of 99mTc-labeled tetrofosmin, separately for myocardium with normal and reduced perfusion, and (2) its influence on quantitative analysis in a 1-day stress-rest protocol. METHODS AND RESULTS: Twenty-five patients with angiographically proved coronary artery disease underwent bicycle exercise stress testing with injection of 200 MBq 99mTc-labeled tetrofosmin and first single-photon emission computed tomographic (SPECT) imaging 40 minutes after injection. A second SPECT was acquired 2.3 +/- 0.4 hours after the first one immediately before rest injection of 800 MBq 99mTc-labeled tetrofosmin. The rest (third) SPECT was acquired 15 minutes thereafter. The relative washout fraction per time (WOFt) was calculated assuming linear washout kinetics. Thirty-three regional uptake values per study were calculated, normalized to the perfusion maximum (100%) in either the postexercise SPECT and the rest SPECT, for the latter with and without correction of remaining counts from stress injection. In regions with normal perfusion, WOFt was 11.5% +/- 3.5% per hour. In regions with markedly reduced perfusion (relative uptake < 50%, WOFt was 8.3% +/- 9.9% per hour. The highest variation of the relative uptake values between rest SPECT with and without correction of remaining counts from stress injection was 5.4% +/- 3.5% in regions with stress-induced ischemia. CONCLUSION: To use a 1-day protocol with a stress-rest radioactivity ratio of 1:4 and an interval of more than 2 hours between the examinations, a correction for remaining counts from stress injection seems not to be necessary for the quantitative analysis of rest SPECT.[Abstract] [Full Text] [Related] [New Search]