Roland Müller-Suur

Comparison of Adenosine and Exercise Stress Test for Quantitative Perfusion Imaging in Patients on Beta-Blocker Therapy

Beta-blocker therapy is used to decrease myocardial ischemia during exercise but may cause suboptimal diagnostic performance in exercise stress testing. The aim of the present study was to compare results of quantitative technetium-99-sestamibi single photon emission tomography (SPECT), following exercise stress test or pharmacological stress test with adenosine. We chose adenosine as comparison, since betablockers may not interfere with adenosine induced vasodilatation and therefore possibly may not interfere with its diagnostic performance. Sixteen patients with angiographically documented coronary disease (5 single-vessel, 6 two-vessel and 5 three-vessel disease), who were chronically treated with beta-blockers, performed SPECT imaging at rest, following bicycle exercise and following adenosine infusion in random order. The SPECT data were analyzed visually and quantitatively, using dedicated computer software (CEqual). According to both visual and quantitative SPECT analysis, adenosine was superior to show reversibility. Higher reversibility extent (50 ± 15 vs. 26 ± 12 pixels, p < 0.01) and more intense reversibility severity (110 ± 29 vs. 49 ± 23 sum of SDs, p < 0.05) were observed during adenosine than exercise. Conclusions: Less myocardial perfusion abnormalities during exercise than during adenosine stress in patients treated with beta-blockers may indicate less ischemia but also an impaired diagnostic performance. Thus adenosine stress test should be preferred to optimize the diagnostic sensitivity in patients during beta-blocker treatment.

Handling of 99mTc-MAG3 in the kidney

The present study was performed to further characterize the renal excretion mechanism for mercaptoacetyltriglycine in comparaison with hyppurate

A Comparative Study of Renal Scintigraphy and Clearance with 99mTc-MAG3 and 123I-Hippurate in Patients with Renal Disorders

The present clinical trial was performed to compare 99m T mercaptoacetyltriglycine with 123 I hippurate since the physical properties of 99m Tc and 123 I are similar